RE: BGP Table and SNMP [7:75016]
Did you read trough the http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps1829/products_feat ure_guide09186a0080087c60.html 12.0 BGP Received Routes MIB http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps1839/products_feat ure_guide09186a0080110bbc.html 12.2T BGP 4 MIB Support for per-Peer Received Routes Martijn -Oorspronkelijk bericht- Van: Alejandro Acosta [mailto:[EMAIL PROTECTED] Verzonden: dinsdag 9 september 2003 3:50 Aan: [EMAIL PROTECTED] Onderwerp: BGP Table and SNMP [7:75016] Hi all, I wonder if any of you have succesfully retrieved the BGP table from a Cisco router using SNMP?. I read a lot of documents and tried a lot of MIBs/OID without any success. I used the MIB navigation tool at the Cisco TAC but I did not find something really useful. I only could read the peerings, uptime of the BGP session and few more thing. By the moment I think it should be done using snmpwalk, am I right? FYI, I do have the full routing table in one of my routers (IOS 12.2.6) Any help will be appreciated. Thank Alejandro Acosta **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=75232&t=75016 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP PEERGROUP PROBLEM [7:74725]
Is it possible to have some sh run, sh ip route, sh ip bgp nei configs please any two will do.You don't have to give away you IDs for Thank you Ollie AT&T Common Backbone 866-397-7309 Opt 1 -Original Message- From: JMC Nel [mailto:[EMAIL PROTECTED] Sent: Wednesday, September 03, 2003 12:53 PM To: [EMAIL PROTECTED] Subject: BGP PEERGROUP PROBLEM [7:74725] Could someone please assist me? I set up a customer to received the Partial TABLE but for some reason the customer is receiving the Full Table. I checked the filter list but that does not seem to be the problem. Any assistance will be greatly appreciated. Thanks GP _ Get MSN 8 and enjoy automatic e-mail virus protection. http://join.msn.com/?page=features/virus **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74731&t=74725 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Re: BGP PEERGROUP PROBLEM [7:74725]
Perhaps a config would be helpful. Or do you expect us to use our psychic abilities to determine the problem? ;-) >>> JMC Nel 9/3/03 12:29:06 PM >>> Could someone please assist me? I set up a customer to received the Partial TABLE but for some reason the customer is receiving the Full Table. I checked the filter list but that does not seem to be the problem. Any assistance will be greatly appreciated. Thanks GP _ Get MSN 8 and enjoy automatic e-mail virus protection. http://join.msn.com/?page=features/virus **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74728&t=74725 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP & Route-maps [7:74424]
Matthew, In your current configuration you have a route-map "com1" with a sequence of 10 in which BGP will look at first as you recieve updates from neighbor R1. Now, within that route map you have specified "match ip address 3", so in acl 3 you are PERMITTING 10.3.2.0/24 and then set acl 3 to expanded community 100.. whatever that states..? (I dont see this in your config for R2). Now if nothing else matches that sequence number 10 then move on to the next sequence number which is "com1 permit 20" in which you are saying that if the route does not match sequence 10 then everything else learned via BGP from that neighbor should match sequence 20 "do not advertise to other peers" in other words, all routes received carrying this value are not advertised to other BGP peers. All in all you have configured this so that you can and will see 10.3.2.0/24 on R2 bgp table for advertising from what I can see.. since you have matched a value for it to do so.. -Sal Matthew Webster wrote: > > Hi all, > > I have a few problems with configuring route maps in > conjunction with BGP. > > I have configured a community that advertises all networks > except two but these two networks are still advertised to the > peer after doing the clear ip bgp * command on both peers. > > I have read in the Cisco book that route-maps are applied to > incoming packets, therefore I need to configure my route-map on > R2, which is connected to R1 over a serial link (R1 has all the > routes to advertise in the BGP AS). > > I'm assuming the logic in my route-map is like this: "if > 10.3.2.0/24 is received in a BGP update, then do not allow that > route to be entered into the BGP route table, however allow all > other routes to be enetered into the BGP route table". Howevere > when I do a sh ip bgp it still includes 10.3.2.0/24. > > Perhaps R2 will still insert the route into its own route > tabel, but not advertise it out to the next router (R3, which > is not connected directly to R1) - does anybody know? Here is > the topology: > > R1--R2---R3 > > Here is the configuration on R2: > > router bgp 100 > no synchronization > neighbor 1.1.1.1 remote-as 100 > neighbor 1.1.1.1 update-source Loopback0 > neighbor 1.1.1.1 send-community > neighbor 1.1.1.1 route-map com1 in > ! > ip classless > ip route 1.1.1.1 255.255.255.255 192.168.100.1 > > access-list 3 permit 10.3.2.0 0.0.0.255 > > route-map com1 permit 10 > match ip address 3 > set community 100 > ! > route-map com1 permit 20 > set community no-advertise > > and on R1: > > interface Ethernet0 > ip address 10.2.2.1 255.255.255.0 secondary > ip address 10.3.2.1 255.255.255.0 secondary > ip address 10.4.2.1 255.255.255.0 secondary > ip address 10.5.2.1 255.255.255.0 secondary > ip address 10.6.2.1 255.255.255.0 secondary > ip address 10.7.2.1 255.255.255.0 secondary > ip address 10.8.2.1 255.255.255.0 secondary > ip address 10.9.2.1 255.255.255.0 secondary > ip address 10.10.2.1 255.255.255.0 secondary > ip address 10.1.2.1 255.255.255.0 > > router bgp 100 > network 10.1.2.0 mask 255.255.255.0 > network 10.2.2.0 mask 255.255.255.0 > network 10.3.2.0 mask 255.255.255.0 > network 10.4.2.0 mask 255.255.255.0 > network 10.5.2.0 mask 255.255.255.0 > network 10.6.2.0 mask 255.255.255.0 > network 10.7.2.0 mask 255.255.255.0 > network 10.8.2.0 mask 255.255.255.0 > network 10.9.2.0 mask 255.255.255.0 > network 10.10.2.0 mask 255.255.255.0 > neighbor 2.2.2.2 remote-as 100 > neighbor 2.2.2.2 update-source Loopback0 > > TIA, > Matthew. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74425&t=74424 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP Connectivity Problem [7:74100]
Not completely on topic, sorry It is about a router, not a pc box. Martijn -Oorspronkelijk bericht- Van: Jansen, M Verzonden: dinsdag 19 augustus 2003 8:15 Aan: Eddie; [EMAIL PROTECTED] Onderwerp: RE: BGP Connectivity Problem [7:74100] What about mobile IP or VPN to border router and get an internal IP for the tftp server's point of view... Just in a typing mood. Martijn -Oorspronkelijk bericht- Van: Eddie [mailto:[EMAIL PROTECTED] Verzonden: maandag 18 augustus 2003 15:06 Aan: [EMAIL PROTECTED] Onderwerp: Re: BGP Connectivity Problem [7:74100] Matthew Webster wrote: > Hi all, > > I have done a sample bgp configuration at r1r2.com. My network setup is as > follows: > > TFTP_Server-(e0)r1(s0)--(s0)r2 > > s0 = 192.168.100.0/24 (.1 for r1, .2 for r2) and e0 = 10.1.4.1/24. > > The problem is that while I can ping the TFTP server (10.1.4.3 from Rtr1's > e0 interface), I can't ping from r2, or from r1's s0 interface. [..] I suppose your TFTP server doesn't have a route entry pointing to the network 192.168.100.0 EC **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74154&t=74100 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP Connectivity Problem [7:74100]
What about mobile IP or VPN to border router and get an internal IP for the tftp server's point of view... Just in a typing mood. Martijn -Oorspronkelijk bericht- Van: Eddie [mailto:[EMAIL PROTECTED] Verzonden: maandag 18 augustus 2003 15:06 Aan: [EMAIL PROTECTED] Onderwerp: Re: BGP Connectivity Problem [7:74100] Matthew Webster wrote: > Hi all, > > I have done a sample bgp configuration at r1r2.com. My network setup is as > follows: > > TFTP_Server-(e0)r1(s0)--(s0)r2 > > s0 = 192.168.100.0/24 (.1 for r1, .2 for r2) and e0 = 10.1.4.1/24. > > The problem is that while I can ping the TFTP server (10.1.4.3 from Rtr1's > e0 interface), I can't ping from r2, or from r1's s0 interface. [..] I suppose your TFTP server doesn't have a route entry pointing to the network 192.168.100.0 EC **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74153&t=74100 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Re: BGP Connectivity Problem [7:74100]
HI Eddie, Fred, thanks for your help...I think this most likely is the problem. As I do not have access to teh TFTP server, I am unable to fix it though. cheers, Matthew. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74130&t=74100 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP Connectivity Problem [7:74100]
The default route on your TFTP server is not set properly. Fred Reimer - CCNA Eclipsys Corporation, 200 Ashford Center North, Atlanta, GA 30338 Phone: 404-847-5177 Cell: 770-490-3071 Pager: 888-260-2050 NOTICE; This email contains confidential or proprietary information which may be legally privileged. It is intended only for the named recipient(s). If an addressing or transmission error has misdirected the email, please notify the author by replying to this message. If you are not the named recipient, you are not authorized to use, disclose, distribute, copy, print or rely on this email, and should immediately delete it from your computer. -Original Message- From: Matthew Webster [mailto:[EMAIL PROTECTED] Sent: Monday, August 18, 2003 7:29 AM To: [EMAIL PROTECTED] Subject: BGP Connectivity Problem [7:74100] Hi all, I have done a sample bgp configuration at r1r2.com. My network setup is as follows: TFTP_Server-(e0)r1(s0)--(s0)r2 s0 = 192.168.100.0/24 (.1 for r1, .2 for r2) and e0 = 10.1.4.1/24. The problem is that while I can ping the TFTP server (10.1.4.3 from Rtr1's e0 interface), I can't ping from r2, or from r1's s0 interface. Here are the configs (I give more if needed) r1#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR Gateway of last resort is not set C192.168.200.0/24 is directly connected, Loopback0 10.0.0.0/24 is subnetted, 1 subnets C 10.1.4.0 is directly connected, Ethernet0 C192.168.100.0/24 is directly connected, Serial0 r1#sh ip bgp BGP table version is 2, local router ID is 192.168.100.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal Origin codes: i - IGP, e - EGP, ? - incomplete Network Next HopMetric LocPrf Weight Path *> 10.1.4.0/24 0.0.0.0 0 32768 i r2#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR Gateway of last resort is not set C192.168.201.0/24 is directly connected, Loopback0 10.0.0.0/24 is subnetted, 1 subnets B 10.1.4.0 [200/0] via 192.168.100.1, 01:18:32 C192.168.100.0/24 is directly connected, Serial0 r2#sh ip bgp BGP table version is 2, local router ID is 192.168.100.2 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal Origin codes: i - IGP, e - EGP, ? - incomplete Network Next HopMetric LocPrf Weight Path *>i10.1.4.0/24 192.168.100.10100 0 i TIA, Matthew. **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74104&t=74100 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Re: BGP Connectivity Problem [7:74100]
Matthew Webster wrote: > Hi all, > > I have done a sample bgp configuration at r1r2.com. My network setup is as > follows: > > TFTP_Server-(e0)r1(s0)--(s0)r2 > > s0 = 192.168.100.0/24 (.1 for r1, .2 for r2) and e0 = 10.1.4.1/24. > > The problem is that while I can ping the TFTP server (10.1.4.3 from Rtr1's > e0 interface), I can't ping from r2, or from r1's s0 interface. [..] I suppose your TFTP server doesn't have a route entry pointing to the network 192.168.100.0 EC Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74106&t=74100 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP and QOS Beta exams [7:73599]
--On 07 August 2003 02:50 + Mwalie W wrote: > > Yes, you will have to begin chasing VUE and Cisco. > Thanks, that is what I thought > > Good Luck! You must be a very patient person:-) And this is also the > reason I do not like Beta exams now. > Actually, I am very impatient. Which is why I try to make a point of only doing Beta's when I dont need the exam, and then trying to ensure I "forget" about the exam. I really had put the exams out of my mind until I saw a couple of groupstudy messages in which people mentioned the results. I dont think there is a problem with my address as I have received results for CCIE Beta qualification exams I took before and after the QOS and BGP exams. Peter Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=73759&t=73599 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
RE: BGP and QOS Beta exams [7:73599]
Peter, Yes, you will have to begin chasing VUE and Cisco. For example, I did BGP Beta on May 30th 2003 and I got a letter about my passing from Prometric around 20th June 2003. After a few days, it also appeared in my Tracking System. The same with BSCI Beta 643-801. It could have something to do with your postal address. So, check with VUE, then they should guide concerning how to approach Cisco ... because my experience shows that Cisco asks for a copy of the result of a given exam, and this comes from Prometric/VUE. Good Luck! You must be a very patient person:-) And this is also the reason I do not like Beta exams now. Mwalie CCDP Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=73637&t=73599 -- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Re: BGP routes [7:71442]
dre wrote: > ""KW S"" wrote in message ... > >>What is the benefits of receiving the following BGP routes >>1. Full routes >>2. Partial routes >>3. No routes > > > Well #3 means it doesn't work (you need at least a default route, or > 0.0.0.0/0), so I'll skip that one... Sure it works, you can configure BGP and recieve no routes but dynamically control your announcements. Dave David Madland CCIE# 2016 Sr. Network Engineer Qwest Communications 612-664-3367 "Government can do something for the people only in proportion as it can do something to the people." -- Thomas Jefferson Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71526&t=71442 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP routes [7:71442]
Hi, Full Routes : That's for your router to maintain anyAS-to-anyAS routing info . If you recv full routes from your ISP then it's more of a disadvantage / overhead . That's so because you'll have to have loads of RAM and CPU power in your ROUTER connecting to the ISP to maintain those routing tables. And there's this problem of instability in another AS ( with which you'd be least bothered ) causing route flaps and interrupts on your BGP router . This issue can be addressed by route summarization and dampening to a good extent . Partial routes : This is typically the case when you are configured to receive only the routes of customers' AS that you'd like to reach and a default route to reach the other AS through your ISP . This reduces the size of your routing table and causes less damage to your BGP router as well as compared to the router receiving full routes . No routes : This is typically like ( if I'm permitted to call !! ) a Totally Stubby Area in the case of OSPF . Your BGP router doesn't recv anything but a default route from your ISP and you don't have much knowledge about any other route. Hope this helps..!! Regards, Srivathsan A -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Thursday, June 26, 2003 8:08 PM To: [EMAIL PROTECTED] Subject: BGP routes [7:71442] Dear all What is the benefits of receiving the following BGP routes 1. Full routes 2. Partial routes 3. No routes Regards, kws Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71509&t=71442 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP routes [7:71442]
""KW S"" wrote in message ... > What is the benefits of receiving the following BGP routes > 1. Full routes > 2. Partial routes > 3. No routes Well #3 means it doesn't work (you need at least a default route, or 0.0.0.0/0), so I'll skip that one... Full routes from two or more providers, with no default route: Benefits - Ability to move any prefix/AS for outbound traffic to any of the providers. Abilty to optimize/maximize loose-mode uRPF features. Ability to optimize/maximize prefix-filters/distribute-lists if you are a transit-AS. Ability to route 0.0.0.0/0 to Null0, aka "The Default Free-Zone, or DFZ" Drawbacks - More routes = more CPU and memory requirements on your routers. However, scaling with today's equipment and a few good configurations makes this a very small issue compared to the power you gain Application - Tier 1 Internet Provider that doesn't receive partial routes from anyone and gets a full routing table from all peers Some Full routes, some Partial routes, no defaults: Benefits - Ability to move any prefix/AS on providers receiving full routes and some ability to move onto providers sending partial routes. Ability to route 0.0.0.0/0 to Null0, which is sort of like "default-free" Drawbacks - Can't use loose-mode uRPF on all providers (but could build a complicated strict-mode uRPF for the partial route providers). Prefix-lists and distribute-lists also become more complicated if you are a transit-AS Application - Tier 2 Internet Providers, Content Providers, any company with IP clue Partial routes from two or more providers, with partial+default route from one provider: Benefits - Ability to move around some prefixes/ASes for outbound traffic to the providers that will take that prefix/AS. Ability to send the rest of your traffic out the default route to the one provider Drawbacks - Restriction to send the rest of your traffic out the default route of only one provider Application - Companies with IP clue that don't have the money to keep all routers configured properly or with enough memory to hold full tables with multiple views Partial routes from two or more providers, with more than one provider sending partial+default routes: Benefits - Ability to move around some prefixes/ASes for outbound traffic to the providers that will take that prefix/AS. Ability to send the rest of your traffic out any of the default routes from the providers you are getting defaults from Drawbacks - More than one default route can be confusing to deal with Application - Companies that don't understand how partial+default works Partial routes from one or more providers, with another single provider providing only a default route: Benefits - As Partial, with partial+default from one provider, only that provider doesn't send partial routes. Drawbacks - Restriction to default route for rest of traffic Application - Companies with IP clue, but very little money and resources (read: only have Cisco 2500 routers or equivalent) Default routes from two or more providers with no full/partial routes: Benefits - you are multihomed (not reliant on one Internet provider), but only in the smallest sense of the term Drawbacks - no ability to influence traffic Applcation - Companies who are willing to spend the extra cost associated with two providers, but aren't willing to upgrade their Cisco 2500 router that has 2MB DRAM -dre Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71484&t=71442 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP routes [7:71442]
i have configured all three for differant requirements. There is no benefit per se, it simply depends on the what your trying to accomplish and how your connected. Dave Justin M. Morgenthaler wrote: > I would assume "Convergence" and the avoidance of this: > > http://www.cisco.com/warp/public/770/fn12942.html > > -Justin M. Morgenthaler > > ""KW S"" wrote in message > news:[EMAIL PROTECTED] > >>Dear all >> >>What is the benefits of receiving the following BGP routes >>1. Full routes >>2. Partial routes >>3. No routes >> >>Regards, kws -- David Madland CCIE# 2016 Sr. Network Engineer Qwest Communications 612-664-3367 "Government can do something for the people only in proportion as it can do something to the people." -- Thomas Jefferson Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71481&t=71442 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP routes [7:71442]
I would assume "Convergence" and the avoidance of this: http://www.cisco.com/warp/public/770/fn12942.html -Justin M. Morgenthaler ""KW S"" wrote in message news:[EMAIL PROTECTED] > Dear all > > What is the benefits of receiving the following BGP routes > 1. Full routes > 2. Partial routes > 3. No routes > > Regards, kws Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71451&t=71442 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
Everybody - thank you. Sorry for this late answer, got stuck with a problem in a remote site for some time. >From what you said I'd think one provider is planning to give us a full BGP feed (but doesn't charge very much), while the other requires a smaller router because they want to filter most routes and charge a lot, I suppose for the (supposed?) continuous tweaking of the routes (what else?). I *assume* (we all know what that means) they think about using a small router at our site, just for redundancy and link switching in case one ISP does lose connectivity, but really won't use BGP at our site for the "best path" selection a lot. This could make sense if both ISP are connected to the rest of internet through the same node at some point, so there wouldn't be any big difference in using one path or the other except for connections to those ISPs itself. However I think although all local ISP do have a interconnection at a node named MIX-IT (Milan, Italy) these major ones all have different long range carriers (to the rest of Europe, to USA and some parts of ASIA if I remember correctly), so I'm still convinced something somewhere stinks, a strategy of that kind would be at best suboptimal. Heiko -- -- PREVINET S.p.A. www.previnet.it -- Heiko Herold [EMAIL PROTECTED] -- +39-041-5907073 ph -- +39-041-5907472 fax > -Original Message- > From: - jvd [mailto:[EMAIL PROTECTED] > Sent: Friday, June 20, 2003 9:50 PM > To: [EMAIL PROTECTED] > Subject: RE: BGP on 1720 ? [7:70960] > > > Hi, > > Just a few thoughts: > > 1. You can use something small like a 1720 to run BGP but the > trick here is > to filter all/some routes that you are receiving. The current > recommendation > from Cisco is 128MB for full BGP routing tables (I think the > tables stand on > 110 000 routes now). The second part would be to advertise > your registered > range to your two ISPs. > > 2. If you want to run full BGP tables you will need a router > with more punch > than the 1720. I did a proposal once with a 2650XM and the > 2691 is also a > good option. Next in line would be your 3640. Of course all > of these models > will need at least 128MB DRAM. > > As I say, just a few thoughts on a lazy Friday afternoon. > > Cheers, Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71350&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: bgp network & sending subnet and more spec [7:71073]
At 01:51 PM 6/24/2003 +, p b wrote: >Someone sent me a pointer off list (thanks Rob) that pointed >me to the "bgp inject-map" command. Yes, that's probably a much better suggestion. Wonder why off list..? Thanks, Zsombor Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71251&t=71073 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: bgp network & sending subnet and more spec [7:71073]
Thanks. Yea, this is a real design. Can't do the /25 statics to the entity that IGP advertises the /24 as there are dual links and multiple hops and certain failure scenarios will cause traffic to get blackholed. Someone sent me a pointer off list (thanks Rob) that pointed me to the "bgp inject-map" command. Looks like it provides a way to get more specifics advertised if only the aggregate exists. Haven't had a chance to confirm this yet, though Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71240&t=71073 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: bgp network & sending subnet and more specifics [7:71073]
Hi, is this only an exercise or you really need to do this? If the latter, then I would be curious to know why this would be useful. I feel a slight contradiction in that you can't control whether a /24 or two /25 routes reach you yet you seem to know what is in one half versus the other half of the /24 network and want to make some routing decision based on this knowledge. Anyway, to answer your question, the obvious solution is to point the two /25 static routes towards where you learn the /24 route from, not to Null0. If you have only one IGP peer, then simply point them towards it. If you have multiple IGP peers, then it gets a bit ugly. You could create a loopback address on the router where x.x.x.x/24 (or the two /25 networks) is directly connected, advertise the loopback(s) through the same IGP protocol which carries the x.x.x.x/24 route, and point the two /25 static routes to the loopback address(es). Or (assuming the IGP is OSPF and x.x.x.x/24 is in another area) you could use the loopback address of some backbone routers (possibly creating multiple pairs of static routes, each with different admin distance pointing to a different backbone router). The main thing to note in either case is that if you ever, for any reason, happen to advertise back these /25 routes towards where you learn the /24 route from, or if the router you pointed your static route to ever thinks that your router is the best way to get to x.x.x.x/24, then you just created a routing loop. Btw, why is it that "the IGP will only send the /24 and not the two /25s"? Getting the two /25s instead of the one /24 might be as easy as configuring a secondary IP address on that interface or (selectively) disabling summarization. This of course depends on your situation, so just something to think about... Thanks, Zsombor At 11:39 PM 6/21/2003 +, p b wrote: >Suppose I have a router which has a subnet x.x.x.0/24 defined >on some interface. Over one iBGP session I'd like to >advertise the x.x.x.0/24 subnet. Over another iBGP session, >I'd like to advertise x.x.x.0/25 and x.x.x.128/25. When >I config three network statements for these subnets in BGP, >only the /24 seems to be sent to the one iBGP peer. > >If I define a static null route for each subnet (x.x.x.0/24, >x.x.x.0/25, and x.x.x.128/25), all three routes are advetised. > >Is there a way to get the /24 and two /25s sent without >the null route? In actuallity, the /24 will be learned >via some IGP, so can't use the nulls and the IGP will >only send the /24 and not the two /25s. > >Thanks Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71210&t=71073 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
At 1:57 PM + 6/22/03, - jvd wrote: >Thank you for your answer Howard. Unfortunately I don't have enough >experience to answer in such depth as you did but maybe one day I'll get >there. :-) > >PS. Isn't it good to see that experts participate in this forum too? > Ah, but you are missing some of the nuances of what the experts say: they _know_ they don't know. Incidentally, we divide the problem into three parts: eBGP convergence (with one and multiple peers, with no policy or route selection modifiers to start), iBGP convergence within an AS, and Internet-wide convergence. Our focus is on the first and second, while some of the best work on the others comes from people like Craig Labovits, the late Abha Ahuja, etc. There's yet a different issue of route stability across the Internet, explored at length in Vern Paxson's PhD dissertation. A little history about how our BGP work got started. One fine day, when I was working at Nortel as a router designer, somebody from sales came running in asking "how many BGP peers can we have?" I started to explain the honest answer of "it depends." It should be pretty intuitive that you can have more peers that are customer routers accepting default and announcing a couple of routes, than you can routers that are exchanging 100,000+ routes. That wasn't what sales wanted to hear. What they wanted to hear simply was that we did more than Juniper. They only wanted that one number, while the reality is that there are lots of things that you can't meaningfully reduce to one number. So, I wrote the first draft of BGP convergence definition, first as an internal document, then as an individual submission from the IETF. Very quickly, we found that engineers at other router and router code manufacturers were being driven crazy by sales as well -- so we rapidly had a team involving Cisco, Nortel, Juniper and NextHop (the last makes OEM router software -- the commercial GateD). Test instrument vendors got interested because they wanted to have a clear measurement to build against. Incidentally, credit where credit is due -- one of the silly things holding up our final publication is an IETF (actually IESG) rule that an RFC can just have five authors. We have six active participants. Alvaro Retana, our team member from Cisco, gracefully volunteered to have his name moved to the acknowledgement section to get around the problem, but he is as major a contributor as anyone else. Unfortunately, we slowed down on the measurement methodology with about half of us losing jobs, being reassigned, etc., but we are hoping to get personal time to finish it. We had three measurement testbeds, at Nortel, Cisco, and NextHop. (No, we aren't going to release the actual numbers--that's not what the IETF is for). It is interesting, however, to find that convergence times will be different, with exactly the same number of routes and other parameters, between a Cisco and a Cisco, a Juniper and a Cisco, a Juniper and a Juniper, etc. There are pure implementer decisions that can slow down -- or in one case speed up -- talking to a router with different internal assumptions on the way you store the Loc-RIB or the order in which you send prefixes in updates. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71093&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
Thank you for your answer Howard. Unfortunately I don't have enough experience to answer in such depth as you did but maybe one day I'll get there. :-) PS. Isn't it good to see that experts participate in this forum too? Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71088&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: bgp network & sending subnet and more specific [7:71073]
Sounds like you may want to disable synchronization to get your routes advertized... Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71079&t=71073 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
A team of us have been drafting IETF documents for a generalized approach to single-router BGP convergence. The terminology document is about to go to the RFC editor after some final text formatting. The methodology document has technically expired--the economy hit the team, but we should be getting back to work. I'll see about posting the drafts, probably at certificationzone.com. The bottom line is that a lot more factors go into even initial convergence than the number of routes, even simplifying to a single peer and no additional policy. Among other things, there will be variation based on the way a given implementation sends its updates (e.g., by order of prefix length, by order of IP address, randomly, etc.) and the particular prefix storage implementation of the receiving router. Another factor will be the number of prefixes packed into each update. Terminology draft: http://www.ietf.org/internet-drafts/draft-ietf-bmwg-conterm-04.txt At 1:08 AM + 6/22/03, Zsombor Papp wrote: >At 08:35 PM 6/21/2003 +, - jvd wrote: >>Hi Zsombor, >> >>The last time I checked BGP was a routing protocol, that means there is an >>algorithm running that's calculating the best path to a destination. A bunch >>of information is advertised to you and your router needs to decide which >>routes to put in the routing table based on the information in the BGP >tables. >> >>So of course you need a processor to do this. > >No doubt about that. :) Holding the routes however doesn't require any >processing. So I am thinking that the sheer number of routes impacts only >the initial convergence time, when the BGP session comes up. This appears >to be far less common than what comes after that, ie. calculating the >effects of continuous routing updates. So the rate of incoming routing >updates seems to be a more important parameter when trying to guesstimate >the CPU utilization. Due to the nature of the best path calculation, >probably the number of peers plays a role, too. I haven't seen these being >mention in the discussion so far, and I was wondering if I am missing >something here. Both the total number of peers and the rate of change at each peer affect convergence after changes. The number affects TCP performance, which is a processor hog. You also run into multiple cases of a change, such as: completely new route route withdrawn and existing less-preferred route now selected route withdrawn and new route learned from a different peer ..and so forth. When you start adding routing policies, the processor load can go up exponentially. > >I glanced through the document you referenced below, that also seems to >talk about memory issues only. > >You haven't answered my question as to how you know that the 1720 is not >fast enough but the 2691 is. Did you do any tests, or have you seen the >1720 fail in a live network due to too many BGP routes? > >Thanks, > >Zsombor > >>Have a look at: >>http://www.cisco.com/en/US/partner/tech/tk365/tk80/technologies_tech_n >>ote09186a0080094a83.shtml >>So of course you need a processor to do this. >> > >Regards, Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71078&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
At 08:35 PM 6/21/2003 +, - jvd wrote: >Hi Zsombor, > >The last time I checked BGP was a routing protocol, that means there is an >algorithm running that's calculating the best path to a destination. A bunch >of information is advertised to you and your router needs to decide which >routes to put in the routing table based on the information in the BGP tables. > >So of course you need a processor to do this. No doubt about that. :) Holding the routes however doesn't require any processing. So I am thinking that the sheer number of routes impacts only the initial convergence time, when the BGP session comes up. This appears to be far less common than what comes after that, ie. calculating the effects of continuous routing updates. So the rate of incoming routing updates seems to be a more important parameter when trying to guesstimate the CPU utilization. Due to the nature of the best path calculation, probably the number of peers plays a role, too. I haven't seen these being mention in the discussion so far, and I was wondering if I am missing something here. I glanced through the document you referenced below, that also seems to talk about memory issues only. You haven't answered my question as to how you know that the 1720 is not fast enough but the 2691 is. Did you do any tests, or have you seen the 1720 fail in a live network due to too many BGP routes? Thanks, Zsombor >Have a look at: >http://www.cisco.com/en/US/partner/tech/tk365/tk80/technologies_tech_n >ote09186a0080094a83.shtml >So of course you need a processor to do this. > >Regards, Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71076&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
Hi Zsombor, The last time I checked BGP was a routing protocol, that means there is an algorithm running that's calculating the best path to a destination. A bunch of information is advertised to you and your router needs to decide which routes to put in the routing table based on the information in the BGP tables. Have a look at: http://www.cisco.com/en/US/partner/tech/tk365/tk80/technologies_tech_n ote09186a0080094a83.shtml So of course you need a processor to do this. Regards, Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71068&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
At 07:50 PM 6/20/2003 +, - jvd wrote: >2. If you want to run full BGP tables you will need a router with more punch >than the 1720. I did a proposal once with a 2650XM and the 2691 is also a >good option. Next in line would be your 3640. Of course all of these models >will need at least 128MB DRAM. How do you decide that a 1720 doesn't have enough "punch" for full BGP tables but a 2691 does? I would think the amount of routes only dictates certain amount of memory. Just because you have a bunch of routes it doesn't necessarily mean you need a faster CPU. Thanks, Zsombor Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71030&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP on 1720 ? [7:70960]
Hi, Just a few thoughts: 1. You can use something small like a 1720 to run BGP but the trick here is to filter all/some routes that you are receiving. The current recommendation from Cisco is 128MB for full BGP routing tables (I think the tables stand on 110 000 routes now). The second part would be to advertise your registered range to your two ISPs. 2. If you want to run full BGP tables you will need a router with more punch than the 1720. I did a proposal once with a 2650XM and the 2691 is also a good option. Next in line would be your 3640. Of course all of these models will need at least 128MB DRAM. As I say, just a few thoughts on a lazy Friday afternoon. Cheers, Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71018&t=70960 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP [7:70881]
hi guys, r1r3---ISP1--- LAN 10.6.0.0| |Internet r2r4---ISP2--- r1, r2, r3 and r4 are running BGP, there is only one path to the Internet and vice versa. Suppose the path is from isp2, r4, r2 how do i change this to isp1, r3,r1 instead. the following are the advertising route captured on both r3 and r4 r4 B 10.6.0.0/16 [20/200] via r2 r3 B 10.6.0.0/16 [200/200] via r1 thanks Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70881&t=70881 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Help! [7:70618]
Think of AS's as countries (not the best analogy but...) If you need to get to the UK from Japan thru the US, then the route would be from Japan >US>UK, right? Now once you land in the US, say in LA, then the US will decide how you will make it to the UK through the US. For ex. US might want you to fly straight to NY and then to London or US might want to first fly to Detroit, then NY and then London or some other way. Thus, AS1 (Japan) knows only of getting to the UK thru the US but cannot dictate how that traffic will get routed thru the US to reach the UK. A little clearer?? ;-> >From: "Mwalie W" >Reply-To: "Mwalie W" >To: [EMAIL PROTECTED] >Subject: RE: BGP Help! [7:70618] >Date: Fri, 13 Jun 2003 06:05:42 GMT > >Hi, > >I have come across that Cisco statement before: I guess it means that one >AS >does not influence the routing policies of another AS :) > >In other words (hoping I am right), AS1 implements its own internal routing >policy, as will AS2 and AS1 will not dictate to AS2 how AS2 should route >AS1's traffic through AS2. > >Honestly, I wish I could get clearer explanation from the members :) _ Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70634&t=70618 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Help! [7:70618]
HI I believe this is about transit AS. If you are doing multihoming with 2-3 ISPs, you do not enable your AS to forward traffic from ISP1 to ISP2 or ISP3. This means you do not make your AS as transit AS. Doing this will enable for eg ISP1 to go to ISP2 using your AS, as that would be a shorter route. HOpe this clarifies Chirag Arora > -Original Message- From: Tiongster 84 [mailto:[EMAIL PROTECTED] Sent: Friday, June 13, 2003 9:52 AM To: [EMAIL PROTECTED] Subject: BGP Help! [7:70618] Hi guys, What does this mean "BGP does not enable one AS to send traffic to a neighbor AS , intending that the traffic take a different route from that taken by traffic originating in the neighbor AS." Thank you very much! DISCLAIMER: Information contained and transmitted by this E-MAIL is proprietary to Wipro Limited and is intended for use only by the individual or entity to which it is addressed, and may contain information that is privileged, confidential or exempt from disclosure under applicable law. If this is a forwarded message, the content of this E-MAIL may not have been sent with the authority of the Company. If you are not the intended recipient, an agent of the intended recipient or a person responsible for delivering the information to the named recipient, you are notified that any use, distribution, transmission, printing, copying or dissemination of this information in any way or in any manner is strictly prohibited. If you have received this communication in error, please delete this mail & notify us immediately at [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70623&t=70618 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Help! [7:70618]
Hi, I have come across that Cisco statement before: I guess it means that one AS does not influence the routing policies of another AS :) In other words (hoping I am right), AS1 implements its own internal routing policy, as will AS2 and AS1 will not dictate to AS2 how AS2 should route AS1's traffic through AS2. Honestly, I wish I could get clearer explanation from the members :) Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70619&t=70618 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Policy-based Routing -- applicable for inbound and [7:70235]
Thanks Jayhawls and Selcuk, the link is usefull to understand more BGP.. cheers hin wrote in message news:[EMAIL PROTECTED] > hi, > > this is nice cisco's page for BGP... > > http://www.cisco.com/univercd/cc/td/doc/cisintwk/ics/icsbgp4.htm > > Selcuk > > > - Original Message - > From: "jayhawks-2003" > To: > Sent: Tuesday, June 03, 2003 9:01 PM > Subject: Re: BGP Policy-based Routing -- applicable for inbound and > [7:70083] > > > > I think you are confusing ip policy routing with BGP policy routing. These > > are > > two DIFFERENT concepts. A BGP routing policy determines what networks a > BGP > > speaking router can receive or advertise to / from a neighboring BGP > > speaking > > router ( IBGP or EBGP ). You use BGP neighbor statements to determine > > inbound > > and outbound policies. This explanation is in a tiny nutshell. BGP offers > a > > variety of tools for route filtering ( communities, AS-PATH, > weightsetc > > ) > > to configure BGP policies. I recommend the book Routing TCP/IP Volumes I & > > II. This would be an excellent start. > > > > Hope this sheds some light > > Go men's Jayhawk basketball!!! Rock-chalk Jayhawk > > > > BB > > > > On Monday 02 June 2003 22:27, Hinwoto wrote: > > > hi guys, > > > > > > Can BGP Policy-based routing be configured both on inbound and outbound > > > interfaces ? > > > I know that it is definitely for inbound interface. > > > And can the policy-based routing also be used to alter the final > > > destination of the packet ? > > > I don't think there's an option to set that. > > > > > > Please, show the light. > > > Thanks guys > > > hin > > > Nondisclosure violations to [EMAIL PROTECTED] > > Virus taramasi Vexira AV programi kullanilarak Is Net tarafindan > yapilmistir. > > This e-mail is checked by Is Net against all known types of viruses using > Vexira AV. > > Is Net'in en ucuz saatlik kullanim paketi Teneffus.Net'i ve en ucuz > sinirsiz erisim paketi Taksitli Ekonet'i duymus muydunuz? > > http://www.isnet.net.tr/teneffusnet/ > > http://www.isnet.net.tr/taksitliekonet/ > > > > > -- > Virus taramasi Vexira AV programi kullanilarak Is Net tarafindan yapilmistir. > This e-mail is checked by Is Net against all known types of viruses using > Vexira AV. > Is Net'in en ucuz saatlik kullanim paketi Teneffus.Net'i ve en ucuz sinirsiz > erisim paketi Taksitli Ekonet'i duymus muydunuz? > http://www.isnet.net.tr/teneffusnet/ > http://www.isnet.net.tr/taksitliekonet/ Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70235&t=70235 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Policy-based Routing -- applicable for inbound and [7:70172]
hi, this is nice cisco's page for BGP... http://www.cisco.com/univercd/cc/td/doc/cisintwk/ics/icsbgp4.htm Selcuk - Original Message - From: "jayhawks-2003" To: Sent: Tuesday, June 03, 2003 9:01 PM Subject: Re: BGP Policy-based Routing -- applicable for inbound and [7:70083] > I think you are confusing ip policy routing with BGP policy routing. These > are > two DIFFERENT concepts. A BGP routing policy determines what networks a BGP > speaking router can receive or advertise to / from a neighboring BGP > speaking > router ( IBGP or EBGP ). You use BGP neighbor statements to determine > inbound > and outbound policies. This explanation is in a tiny nutshell. BGP offers a > variety of tools for route filtering ( communities, AS-PATH, weightsetc > ) > to configure BGP policies. I recommend the book Routing TCP/IP Volumes I & > II. This would be an excellent start. > > Hope this sheds some light > Go men's Jayhawk basketball!!! Rock-chalk Jayhawk > > BB > > On Monday 02 June 2003 22:27, Hinwoto wrote: > > hi guys, > > > > Can BGP Policy-based routing be configured both on inbound and outbound > > interfaces ? > > I know that it is definitely for inbound interface. > > And can the policy-based routing also be used to alter the final > > destination of the packet ? > > I don't think there's an option to set that. > > > > Please, show the light. > > Thanks guys > > hin > > Nondisclosure violations to [EMAIL PROTECTED] > Virus taramasi Vexira AV programi kullanilarak Is Net tarafindan yapilmistir. > This e-mail is checked by Is Net against all known types of viruses using Vexira AV. > Is Net'in en ucuz saatlik kullanim paketi Teneffus.Net'i ve en ucuz sinirsiz erisim paketi Taksitli Ekonet'i duymus muydunuz? > http://www.isnet.net.tr/teneffusnet/ > http://www.isnet.net.tr/taksitliekonet/ > -- Virus taramasi Vexira AV programi kullanilarak Is Net tarafindan yapilmistir. This e-mail is checked by Is Net against all known types of viruses using Vexira AV. Is Net'in en ucuz saatlik kullanim paketi Teneffus.Net'i ve en ucuz sinirsiz erisim paketi Taksitli Ekonet'i duymus muydunuz? http://www.isnet.net.tr/teneffusnet/ http://www.isnet.net.tr/taksitliekonet/ Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70172&t=70172 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Policy-based Routing -- applicable for inbound and [7:70083]
I think you are confusing ip policy routing with BGP policy routing. These are two DIFFERENT concepts. A BGP routing policy determines what networks a BGP speaking router can receive or advertise to / from a neighboring BGP speaking router ( IBGP or EBGP ). You use BGP neighbor statements to determine inbound and outbound policies. This explanation is in a tiny nutshell. BGP offers a variety of tools for route filtering ( communities, AS-PATH, weightsetc ) to configure BGP policies. I recommend the book Routing TCP/IP Volumes I & II. This would be an excellent start. Hope this sheds some light Go men's Jayhawk basketball!!! Rock-chalk Jayhawk BB On Monday 02 June 2003 22:27, Hinwoto wrote: > hi guys, > > Can BGP Policy-based routing be configured both on inbound and outbound > interfaces ? > I know that it is definitely for inbound interface. > And can the policy-based routing also be used to alter the final > destination of the packet ? > I don't think there's an option to set that. > > Please, show the light. > Thanks guys > hin > Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=70083&t=70083 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Beta Exam - Thorough! [7:69644]
Glad to help !! Hope it was worth it towards your BGP learning process and towards your CCIP!! Based on the many Cisco exams that I have taken, BGP was the most extensive and thorough exam (becoz' it is a beta) but it does really test your knowledge on it, right? And the second most difficult after Qos/Mcast exam Good Luck towards your CCIP path.MPLS is not that bad though!! Sincerely, CN >From: "Mwalie W" >Reply-To: "Mwalie W" >To: [EMAIL PROTECTED] >Subject: BGP Beta Exam - Thorough! [7:69644] >Date: Wed, 28 May 2003 06:49:49 GMT > >Hi All, > >Today, I did BGP Beta towards CCIP. > >A very thorough exam, with some bugs and grammatical mistakes here and there. > >It is so thorough and long that if you are not well prepared, you will pass >with difficulty. No time to thinkeven a faster reader like me had >problems. > >The first question took me about 10 minutes (should take about 1.5 minutes). >From then on, I knew that I was always going to struggle. > >It is a nice exam to prepare for, full of diagrams and configurations! We >need such kind of exams for certifying competent professionals. > >If I do not pass, I will gladly have the same experience again. Very nice >intellectual challenge, I thought! > >To Cisco Nuts, Thanks for the hints!! I appreciate that so much. > >Good misconduct and Nondisclosure violations to [EMAIL PROTECTED] Tired of spam? Get advanced junk mail protection with MSN 8. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69814&t=69644 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Beta Exam - Thorough! [7:69644]
Hi, I really appreciate your help.:). Ill let you know about how i fared tomorrwow. Thanks a zillion!!! Regards Shahryar Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69777&t=69644 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
Thanks Tom.. good explanation! This was my thought to the tee.. Yes I agree with cisco that it does not hurt to add it to add value to the design.. But as you just stated.. "ebgp-multihop is NOT necessary for load balancing" That was my point all along.. Just wanted to clarify my point so I am not mistaken.. Thanks!! Sal Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69769&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
Salvatore, ebg-multihop is not required for load balancing. It can be beneficial to use a loopback to peer from/to, similar to IPX internal networks provide better load balancing for NetWare servers. If you feel it's a good idea to peer to/from loopack interfaces (redundancy, better balancing) then you'll need ebgp-multihop since you are adding hops. If you have multiple directly connected interfaces to the BGP neighbor and don't use loopback interfaces, you don't need ebgp-multihop. - Tom Salvatore De Luca wrote: > Understood.. but does the command "neigh x.x.x.x ebgp-multihop X" by itself > provide load-balancing? I could be wrong.. but from my undrstanding this > just states that you have the capability of peering with neigh that are not > directly connected.. You could very well acheive loadbalancing when 2 EBGP > routers peer with its neighbors loopbacks.. Yes.. in this case you would > need to be directly connected.. so why would you need neigh x.x.x.x > ebgp-multihop... Please enlighten me with your thoughts.. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69755&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
Understood.. but does the command "neigh x.x.x.x ebgp-multihop X" by itself provide load-balancing? I could be wrong.. but from my undrstanding this just states that you have the capability of peering with neigh that are not directly connected.. You could very well acheive loadbalancing when 2 EBGP routers peer with its neighbors loopbacks.. Yes.. in this case you would need to be directly connected.. so why would you need neigh x.x.x.x ebgp-multihop... Please enlighten me with your thoughts.. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69736&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Re: BGP Load Balance [7:69611]
BGP load balancing can be done using BGP peering on loopback address .And you have to add static routes in your routing table for loopback ip address and mention next-hop as serial links ip addresses/serial interface example: nei loopbackip remote-as asnumber nei loopbackip ebgp-multihop number and then ip route loopback ip 255.255.255.255 serialx ip route loopback ip 255.255.255.255 serialy hope this will help you Ramesh "Brian W." wrote: The way I've seen 2 paths used is by peering with a loopback interface and using neighbor peerip ebgp-multihop in the config. Brian - Original Message - From: "Azhar Teza" To: Sent: Tuesday, May 27, 2003 3:16 PM Subject: BGP Load Balance [7:69611] > If BGP route has two equal paths to the same destination, can it do load > balance by installing the command? maximum-paths 2 > > ___ > Join Excite! - http://www.excite.com > The most personalized portal on the Web! Get Your Private, Free E-mail from Indiatimes at http://email.indiatimes.com Buy The Best In BOOKS at http://www.bestsellers.indiatimes.com Bid for Air Tickets @ Re.1 on Air Sahara Flights. Just log on to http://airsahara.indiatimes.com and Bid Now ! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69671&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
Folllowing on from everyone else, we often make use of loopbacks for internal peering, that way you will always have redundant paths to iBGP peers, however when peering with external peers / isp we make use of the external facing interface ip. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69661&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
No - Original Message - From: "Azhar Teza" To: Sent: Tuesday, May 27, 2003 11:16 PM Subject: BGP Load Balance [7:69611] > If BGP route has two equal paths to the same destination, can it do load > balance by installing the command? maximum-paths 2 > > ___ > Join Excite! - http://www.excite.com > The most personalized portal on the Web! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69651&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Beta Exam - Thorough! [7:69644]
Hi, I am also taking it on 30th. Can you please advice me a little bit further on the format. Are there any simulation based questions?? Regards ShahryarMwalie W wrote: > > Hi All, > > Today, I did BGP Beta towards CCIP. > > A very thorough exam, with some bugs and grammatical mistakes > here and there. > > It is so thorough and long that if you are not well prepared, > you will pass with difficulty. No time to thinkeven a > faster reader like me had problems. > > The first question took me about 10 minutes (should take about > 1.5 minutes). From then on, I knew that I was always going to > struggle. > > It is a nice exam to prepare for, full of diagrams and > configurations! We need such kind of exams for certifying > competent professionals. > > If I do not pass, I will gladly have the same experience again. > Very nice intellectual challenge, I thought! > > To Cisco Nuts, Thanks for the hints!! I appreciate that so much. > > Good Luck! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69650&t=69644 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
Yes you can load-balance traffic to the same destination over 2 equal logical paths using "maximum-paths 2" Using Loopback address ip to peer and acheive load-balancing to the same destination will require either to use process-switching - not recommended - or enable CEF and do " per-packet load-balancing " Regards, Yasser >From: "Brian W." >The way I've seen 2 paths used is by peering with a loopback interface and >using >neighbor peerip ebgp-multihop in the config. > > Brian > >- Original Message - >From: "Azhar Teza" >To: >Sent: Tuesday, May 27, 2003 3:16 PM >Subject: BGP Load Balance [7:69611] > > > > If BGP route has two equal paths to the same destination, can it do load > > balance by installing the command? maximum-paths 2 > > > > ___ > > Join Excite! - http://www.excite.com > > The most personalized portal on the Web! _ Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69645&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
heres the cisco guide on it. http://www.cisco.com/univercd/cc/td/doc/cisintwk/ics/icsbgp4.htm#2351 Bri - Original Message - From: "Salvatore De Luca" To: Sent: Tuesday, May 27, 2003 7:15 PM Subject: Re: BGP Load Balance [7:69611] > I personally prefer Peering with Loops myself.. the EBGP multihop command > has absolutley nothing to do with loadbalancing. It it used for peering with > neighbors whom are not directly connected.. There are various ways of > performing BGP load balancing.. Metric..route-maps.. etc.. Pick your flavor. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69646&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
I personally prefer Peering with Loops myself.. the EBGP multihop command has absolutley nothing to do with loadbalancing. It it used for peering with neighbors whom are not directly connected.. There are various ways of performing BGP load balancing.. Metric..route-maps.. etc.. Pick your flavor. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69632&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Load Balance [7:69611]
The way I've seen 2 paths used is by peering with a loopback interface and using neighbor peerip ebgp-multihop in the config. Brian - Original Message - From: "Azhar Teza" To: Sent: Tuesday, May 27, 2003 3:16 PM Subject: BGP Load Balance [7:69611] > If BGP route has two equal paths to the same destination, can it do load > balance by installing the command? maximum-paths 2 > > ___ > Join Excite! - http://www.excite.com > The most personalized portal on the Web! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69622&t=69611 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
At 01:53 AM 4/6/2003 +, Bullwinkle wrote: >In other words, for purposes of testing, there are ONLY two ways to remove >things from the AS_PATH. 1) the technique you describe, which is to create Both these techniques are invalid in my opinion. If you create a new route, you haven't changed the AS-PATH on another route at all. In these cases, you have two routes, not one modified one. >an aggregate and advertise that aggregate only ( although refresh my >memory - an aggregate might still contain full AS_PATH information - don't >have my book handy ) OR to create an appropriate route to null 0, then enter >that route into the BGP process, while filtering those that contain the >AS_PATH you want to remove. > > >AS1-AS2-AS3 > >192.168.x.x subnets --advertised into AS2 > > ip route 192.0.0.0 255.0.0.0 >null 0 >bgp process command: network 192.0.0.0 mask 255.0.0.0 > >filter the more specific BGP routes. > >AS3 should see just the route to null 0, which does originate in AS2 > >do I have that right? Do you agree? > >-- >- > >Bullwinkle: Hey, Rocky, watch me pull a CCIE out of my hat! > >Rocky: Bullwinkle, that trick NEVER works > >Bullwinkle: This time FOR SURE!!! >( pulls snarling Proctor out of hat ) >No doubt about it. I gotta get me a new hat! > > > >""Salvatore De Luca"" wrote in message >news:[EMAIL PROTECTED] > > I hear ya.. that's why if this was a TEST situation, the statement: > > > > ip as-path access-list 1 permit _2_ & ! _2_ _1$ would permit routes > > traversing AS2 but deny any routes traversed though AS2 Originating in >AS1. > > In which case 150.50.200.0 aggregated element should be the nlri "Fresh > > Route" point for AS3's knowledge. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66965&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
Agreed by me.. the trick is it seems that we want to remove AS1 from the AS-path without filtering the whole IP Block. As long as AS2 Can Create the route you want advertised to R3,(Network Statments pointing to Null route injections will do this and put it in the BGP table). You can then filter routes originating in AS1 that has to traverse AS2 to get to AS3, without disrupting routes originated in other AS's besides AS1 that DO traverse AS2 to get to AS3. This is plain vanilla as-path filtering to me. EX: (routesnotwanted) (routeswanted)--> AS1--->AS2-->AS3 / / / / / AS4---^ (routeswanted) If the main objective is to filter routes orgininating in AS1 but not 2 then, _200_ & ! _200_ 100$ is a way to go. You then just have to keep in mind where the routes get originated. All the best, Sal Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66949&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
In other words, for purposes of testing, there are ONLY two ways to remove things from the AS_PATH. 1) the technique you describe, which is to create an aggregate and advertise that aggregate only ( although refresh my memory - an aggregate might still contain full AS_PATH information - don't have my book handy ) OR to create an appropriate route to null 0, then enter that route into the BGP process, while filtering those that contain the AS_PATH you want to remove. AS1-AS2-AS3 192.168.x.x subnets --advertised into AS2 ip route 192.0.0.0 255.0.0.0 null 0 bgp process command: network 192.0.0.0 mask 255.0.0.0 filter the more specific BGP routes. AS3 should see just the route to null 0, which does originate in AS2 do I have that right? Do you agree? -- - Bullwinkle: Hey, Rocky, watch me pull a CCIE out of my hat! Rocky: Bullwinkle, that trick NEVER works Bullwinkle: This time FOR SURE!!! ( pulls snarling Proctor out of hat ) No doubt about it. I gotta get me a new hat! ""Salvatore De Luca"" wrote in message news:[EMAIL PROTECTED] > I hear ya.. that's why if this was a TEST situation, the statement: > > ip as-path access-list 1 permit _2_ & ! _2_ _1$ would permit routes > traversing AS2 but deny any routes traversed though AS2 Originating in AS1. > In which case 150.50.200.0 aggregated element should be the nlri "Fresh > Route" point for AS3's knowledge. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66943&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
I hear ya.. that's why if this was a TEST situation, the statement: ip as-path access-list 1 permit _2_ & ! _2_ _1$ would permit routes traversing AS2 but deny any routes traversed though AS2 Originating in AS1. In which case 150.50.200.0 aggregated element should be the nlri "Fresh Route" point for AS3's knowledge. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66940&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Question...?? [7:66919]
You are both right.. but the problem scenario does'nt give you that mutch info.. I am trying to deduce all and any ways of going about possible peering 128.1.1.254. The scenario does not specify if it is a directly connected peer on the lan segment. That is why I tried updating the source to the Ethernet first 128.1.2.3 which did not work. You can peer with secondary addresses with BGP, but I dont think that's what they are asking for. Since the information is limited with just "Address 128.1.2.3 should be used for peering with 128.1.1.254." I thought this was a bit vauge, but since I dont know exactly how many hops 128.1.1.254 is: neighbor 128.1.1.254 ebgp-multihop 255 will have to do. The thing that threw me off was when it stated to use the Ethernet ip address 128.1.2.3 for peering?? Thanks for the feedback... Sal Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66939&t=66919 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Question...?? [7:66919]
At 03:46 PM 4/5/2003 +, Salvatore De Luca wrote: >Hi All, > > I am trying to better understand a particular BGP scenario, thought >someone might shed some light. This is probably very simple, i am just >missing the punchline. If you have 2 routers, one let's say running in AS100 >the other running in AS200, and you had to EBGP peer with 128.1.1.254 from >AS100 router. You were required to use the Ethernet0/0 ip on AS100 router >for peering 128.1.2.3, would you configure your neighbor statment pointing >to 128.1.1.254 and update the source to Ethernet 0/0?,(I tried this and was >no good) even after a debug ip bgp. I think maybe a secondary address >128.1.1.253 on the ethernet might be a way to go. Basically, 128.1.1.254 is >a route generator that I would need to peer with in order to recieve several >external routes. I dont have any configs to post at the moment, but just >trying to get an outside opinion. There isn't enough info here to answer this. Is 128.1.1.254 on the other side of the Ethernet? (ie the next is 128.1.0.0/22)? Likely not I expect. If not, you need to use EBGP multihop which will allow the EBGP packets to move out farther than 1 link (changes the TTL in the packet from 1 to whatever you set it to) Furthermore, is the 128.1.1.254 configured to peer with 128.1.2.3? If not, you'll need to use "update source" to set your side of the connection to the appropriate address. If 128.1.2.3 is a secondary, that this would likely need to be used as well. However, is 128.1.2.3 is the primary address on the eth0 and the eth0 is the closest link on your router toward 128.1.1.254 and 128.1.1.254 is set to peer with 128.1.2.3, than you should just be able to set multi-hop with an appropriate TTL and be on your way. Also watch for BGP authentication in case it is required. Pete >Thanks, >Static0101 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66937&t=66919 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
At 08:26 PM 4/5/2003 +, Salvatore De Luca wrote: >I have to agree that it is a bit silly, dangerous, and should not be done on >a production enviornment.. but so are a lot of scenarios on the CCIE Lab.. >Just to add to the sillyness: Because it is silly and dangerous, you also can't do it without creating an entirely fresh route with the same nlri and conditionally advertising it somehow. You simply are not supposed to muck with AS-PATH elements unless you are aggregating, it which case you follow the defined guidelines. >Not sure how this would work, but you can try it.. have you tried as-path >manupulation? From what I can see you want to remove as 1 from the path as >R3 see's it. This config may work for what you are looking to do. You can >try applying this to the config aggregating the 150.50.200.0 network. I >think AS2 would have to originate the 150.50.200.0 net. > > >router bgp 3 >neighbor x.x.x.x route-map as-path in > > >route-map as-path permit 10 >match as-path 1 >route-map as-path permit 20 >match as-path 2 > > ip as-path access-list 1 permit _2_ & ! _2_ _1$ > ip as-path access-list 2 permit .* > >Sal Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66938&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
At 04:22 PM 4/2/2003 -0500, you wrote: >150.50.200.0(R1)(R2)--(R3). > >R1 belongs to AS1 >R2 belongs to AS2 >R3 belongs to AS3 > >I inject 150.50.200.0 using the network command on R1 and see 150.50.200.0 >in R3 with as_path of 2 1. > >The question is how can I remove the 1 from the As Path on R3. You don't. Doing this would be silly and likely dangerous. >I have tried using the network command on R2 with no success. >If I aggregate on R2 using 150.50.200.0 255.255.255.0 summary-only , I >will still see 150.50.200.0 with as-path 2 1 ( no change). >However, if I aggregate on R2 using 150.50.0.0 255.255.0.0 summary-only, >then I will see 150.50.0.0 with as-path 2. The question was to get >150.50.200.0 and not 150.50.0.0. > >I can't get the 150.50.200.0 to work. > > >Thank you. > >RAM Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66928&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP AS removal [7:66928]
I have to agree that it is a bit silly, dangerous, and should not be done on a production enviornment.. but so are a lot of scenarios on the CCIE Lab.. Just to add to the sillyness: Not sure how this would work, but you can try it.. have you tried as-path manupulation? From what I can see you want to remove as 1 from the path as R3 see's it. This config may work for what you are looking to do. You can try applying this to the config aggregating the 150.50.200.0 network. I think AS2 would have to originate the 150.50.200.0 net. router bgp 3 neighbor x.x.x.x route-map as-path in route-map as-path permit 10 match as-path 1 route-map as-path permit 20 match as-path 2 ip as-path access-list 1 permit _2_ & ! _2_ _1$ ip as-path access-list 2 permit .* Sal Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66930&t=66928 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Question...?? [7:66919]
unless the peers are on the same segment, you also need the neighbor ebgp-multihop command configured on both routers. HTH -- - Bullwinkle: Hey, Rocky, watch me pull a CCIE out of my hat! Rocky: Bullwinkle, that trick NEVER works Bullwinkle: This time FOR SURE!!! ( pulls Rocky out of hat ) Well, I'm getting closer! ""Salvatore De Luca"" wrote in message news:[EMAIL PROTECTED] > Hi All, > > I am trying to better understand a particular BGP scenario, thought > someone might shed some light. This is probably very simple, i am just > missing the punchline. If you have 2 routers, one let's say running in AS100 > the other running in AS200, and you had to EBGP peer with 128.1.1.254 from > AS100 router. You were required to use the Ethernet0/0 ip on AS100 router > for peering 128.1.2.3, would you configure your neighbor statment pointing > to 128.1.1.254 and update the source to Ethernet 0/0?,(I tried this and was > no good) even after a debug ip bgp. I think maybe a secondary address > 128.1.1.253 on the ethernet might be a way to go. Basically, 128.1.1.254 is > a route generator that I would need to peer with in order to recieve several > external routes. I dont have any configs to post at the moment, but just > trying to get an outside opinion. > > Thanks, > Static0101 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66926&t=66919 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
At 04:52 PM 3/31/2003 +, \"\"[EMAIL PROTECTED]"\" wrote: >All, > >Please can someone clear this up for me, if you have the time. > >IBGP peers do not have to be physically connected to one another, as long as >an IGP (most preferably) is running between them. In most cases the routers are not adjacent and certainly do not need to be. Half the reason one runs an IGP in an ISP is for loopback reachability support for IBGP peering. Such a demand would put pretty expensive topological demands on a network. >On page 128 (paragraph 1) of the Routing TCP/IP Volume 2 book, it says the >following about route reflectors and clients :- >"The clients have physical connections to each of the route reflectors, and >they peer to each" This may relate only to the diagram in question. >I assume that each client in a iBGP domain, does not need to share a >physical data-link to each RR? Correct. >Many thx. (maybe im just tired from studying all weekend). > >Regards, >Ken > > > >For more information about Barclays Capital, please >visit our web site at http://www.barcap.com. > > >Internet communications are not secure and therefore the Barclays >Group does not accept legal responsibility for the contents of this >message. Although the Barclays Group operates anti-virus programmes, >it does not accept responsibility for any damage whatsoever that is >caused by viruses being passed. Any views or opinions presented are >solely those of the author and do not necessarily represent those of the >Barclays Group. Replies to this email may be monitored by the Barclays >Group for operational or business reasons. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66573&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Route Reflectors [7:66488]
Wellthat is what the book says. Try it out on your own lab and you will see that a Route-reflector client does not have to be directly connected to the Route-reflector for it to work. Just tried it in my home lab and it works, the client is 3 routers away. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66564&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Route Reflectors [7:66488]
Thx to all who replied. Make sense now :)) Beers to all! -Original Message- From: The Long and Winding Road [mailto:[EMAIL PROTECTED] Sent: 31 March 2003 05:33 To: [EMAIL PROTECTED] Subject: Re: BGP Route Reflectors [7:66488] ""Mike Martins"" wrote in message news:[EMAIL PROTECTED] > Yes, EBGP multihop is between different AS's, that is a different > setup, it > must also have a way of reaching across the hops, an IGP. nope - works just fine for iBGP as well. > > On a IBGP you can have a hop across ie 5 routers in a IBGP peering session. ?? anyBGP assumes it's neighbor is directly connected - i.e. on the same segment. The EBGP-multihop command changes the TTL to whatever the configured hop count is. ( default 255 ) Refer to RFC 1771 for the specification. > As long as the IGP can reach the other peer it will work. Also, the > full mesh requirement of IBGP is in logical and not physical links. In > other words if you had 5 routers fully meshed each router would need 4 > neighbour statments. And then consider the amount of BGP updates > running to and fro, that is why route-reflectors are used, to minimize > peering sessions. different issue. For more information about Barclays Capital, please visit our web site at http://www.barcap.com. Internet communications are not secure and therefore the Barclays Group does not accept legal responsibility for the contents of this message. Although the Barclays Group operates anti-virus programmes, it does not accept responsibility for any damage whatsoever that is caused by viruses being passed. Any views or opinions presented are solely those of the author and do not necessarily represent those of the Barclays Group. Replies to this email may be monitored by the Barclays Group for operational or business reasons. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66542&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
""Mike Martins"" wrote in message news:[EMAIL PROTECTED] > Yes, EBGP multihop is between different AS's, that is a different setup, it > must also have a way of reaching across the hops, an IGP. nope - works just fine for iBGP as well. > > On a IBGP you can have a hop across ie 5 routers in a IBGP peering session. ?? anyBGP assumes it's neighbor is directly connected - i.e. on the same segment. The EBGP-multihop command changes the TTL to whatever the configured hop count is. ( default 255 ) Refer to RFC 1771 for the specification. > As long as the IGP can reach the other peer it will work. Also, the full > mesh requirement of IBGP is in logical and not physical links. In other > words if you had 5 routers fully meshed each router would need 4 neighbour > statments. And then consider the amount of BGP updates running to and fro, > that is why route-reflectors are used, to minimize peering sessions. different issue. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66533&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
Yes, EBGP multihop is between different AS's, that is a different setup, it must also have a way of reaching across the hops, an IGP. On a IBGP you can have a hop across ie 5 routers in a IBGP peering session. As long as the IGP can reach the other peer it will work. Also, the full mesh requirement of IBGP is in logical and not physical links. In other words if you had 5 routers fully meshed each router would need 4 neighbour statments. And then consider the amount of BGP updates running to and fro, that is why route-reflectors are used, to minimize peering sessions. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66516&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
The Long and Winding Road wrote: > > wrote in message > news:[EMAIL PROTECTED] > > All, > > > > Please can someone clear this up for me, if you have the time. > > > > IBGP peers do not have to be physically connected to one > another, as long > as > > an IGP (most preferably) is running between them. > > > nope. direct connect is preferred, but nope - don't have to be > > > > > > On page 128 (paragraph 1) of the Routing TCP/IP Volume 2 > book, it says the > > following about route reflectors and clients :- > > "The clients have physical connections to each of the route > reflectors, > and > > they peer to each" > > preferred but not necessary. that's why there is an "neighbor > ebgp-multihop" I thought "ebgp-multihop" was for neighbors in different AS's ? Going right now to check it on the command reference ... > command :-> > > > > > > I assume that each client in a iBGP domain, does not need to > share a > > physical data-link to each RR? > > > nope > > > > > Many thx. (maybe im just tired from studying all weekend). > > > > Regards, > > Ken > > > > > > > > > For more information about Barclays Capital, please > > visit our web site at http://www.barcap.com. > > > > > > Internet communications are not secure and therefore the > Barclays > > Group does not accept legal responsibility for the contents > of this > > message. Although the Barclays Group operates anti-virus > programmes, > > it does not accept responsibility for any damage whatsoever > that is > > caused by viruses being passed. Any views or opinions > presented are > > solely those of the author and do not necessarily represent > those of the > > Barclays Group. Replies to this email may be monitored by > the Barclays > > Group for operational or business reasons. > > > > > > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66514&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
A practise that is becoming quite common is running BGP on the edges of an AS only. It is a waste for a router in the core to have a full internet table. The Core could then comprise of ie MPLS which would optimize the traffic flows. I cannot remember which book I used but when I was studying for the CCNP I read somewhere that IBGP routes have to be 'physically connected', this is untrue of course. As long as the IGP can reach the IBGP peer it is fine. The problem is that these misinterpretations stick. For a month or so before I was corrected I actually thought that a physical connection was a requirement. There is also something else to consider; the way one book I read worded a section on Route-reflectors and Confederations made it sound like you could only use either or, not both. This is untrue of course, you can use Route-reflectors inside a confederation. Just a note. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66510&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
Ken, Technically speaking, even eBGP has the ability to peer with neighbors that aren't directly connected. Typically, eBGP peers will have diect physical connectivity, whereas iBGP peers are part of the same AS, as long as a route/path exist to that peer, connectivity shouldn't be a problem. When you address this issue, think of the requirement for BGP to be sync'd with the IGP for route information to be advertised. As well as the limitations/features of the peering relationship from one AS to another, or devices within the same AS. HTH Nigel - Original Message - From: To: Sent: Sunday, March 30, 2003 9:10 AM Subject: BGP Route Reflectors [7:66488] > All, > > Please can someone clear this up for me, if you have the time. > > IBGP peers do not have to be physically connected to one another, as long as > an IGP (most preferably) is running between them. > > On page 128 (paragraph 1) of the Routing TCP/IP Volume 2 book, it says the > following about route reflectors and clients :- > "The clients have physical connections to each of the route reflectors, and > they peer to each" > > I assume that each client in a iBGP domain, does not need to share a > physical data-link to each RR? > > Many thx. (maybe im just tired from studying all weekend). > > Regards, > Ken > > > > For more information about Barclays Capital, please > visit our web site at http://www.barcap.com. > > > Internet communications are not secure and therefore the Barclays > Group does not accept legal responsibility for the contents of this > message. Although the Barclays Group operates anti-virus programmes, > it does not accept responsibility for any damage whatsoever that is > caused by viruses being passed. Any views or opinions presented are > solely those of the author and do not necessarily represent those of the > Barclays Group. Replies to this email may be monitored by the Barclays > Group for operational or business reasons. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66497&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflectors [7:66488]
wrote in message news:[EMAIL PROTECTED] > All, > > Please can someone clear this up for me, if you have the time. > > IBGP peers do not have to be physically connected to one another, as long as > an IGP (most preferably) is running between them. nope. direct connect is preferred, but nope - don't have to be > > On page 128 (paragraph 1) of the Routing TCP/IP Volume 2 book, it says the > following about route reflectors and clients :- > "The clients have physical connections to each of the route reflectors, and > they peer to each" preferred but not necessary. that's why there is an "neighbor ebgp-multihop" command :-> > > I assume that each client in a iBGP domain, does not need to share a > physical data-link to each RR? nope > > Many thx. (maybe im just tired from studying all weekend). > > Regards, > Ken > > > > For more information about Barclays Capital, please > visit our web site at http://www.barcap.com. > > > Internet communications are not secure and therefore the Barclays > Group does not accept legal responsibility for the contents of this > message. Although the Barclays Group operates anti-virus programmes, > it does not accept responsibility for any damage whatsoever that is > caused by viruses being passed. Any views or opinions presented are > solely those of the author and do not necessarily represent those of the > Barclays Group. Replies to this email may be monitored by the Barclays > Group for operational or business reasons. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66493&t=66488 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP exam in prep. for the CCIE Lab!! [7:66432]
Willy. Wow!! you teach the BGP and MPLS courses!! Where??? Awesome!! I've just begun my MPLS study which will be the last exam for the CCIP...Then I am going to head back to study for the CCIE Lab which I will take once Mr. Solie comes out with his PSV II .. When Mr. Solie ?? :-) I have 2 study guides from Cisco for the MPLS: one that says MPLS Concepts and the other that says MPLS/VPNDo I need to study both of these for the MPLS exam or just the first one will suffice? If both, then do I need any additional books from Cisco Press to supplement what I have? Like Advanced VPN by Allwyn or MPLS Traffic Engineering book?? Thank you for your help. Sincerely, CN >From: "Willy Schoots" >To: "'Cisco Nuts'" >Subject: RE: BGP exam in prep. for the CCIE Lab!! [7:66432] >Date: Sat, 29 Mar 2003 17:03:12 +0100 > >Hi CN, > >I took the beta exam some while back (begin of February). I found it a >relatively easy exam for someone that has followed the course (CBCR / >BGP 3.0). The reason that I found it easy is because there are no >questions not covered in the course and also not too many >strange/unclear questions. > >I agree with you that it had a lot of questions with diagrams and that >therefore the time was a constraint. > >Cheers, > >Willy Schoots > >PS: My judgment may colored by the fact that I teach this course and >that it is one of my favorite courses to teach (together with the MPLS >course). > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of >Cisco Nuts >Sent: zaterdag 29 maart 2003 14:58 >To: [EMAIL PROTECTED] >Subject: BGP exam in prep. for the CCIE Lab!! [7:66432] > >Hello,The new BGP exam(beta) for the CCIP exam is a great one (imho) in >prep. for the actual CCIE Lab.It really tests your skill and deep >understanding of your BGP knowledge..133 questions in 250 minutes >(slightly less than 2 minutes per question), which I think was not >enough.Diagrams after diagrams.The testing site refused to give >me just plain white sheets of paper and also refused for me to take my >color pens, even my normal pens!!.. So it was a real 'drag' trying >to >draw diagrams in the provided "plastic sheets" as it smudges and no >place >to write but on my knees!!. Reminded me so much of that 'dreaded >place' that many us have been or will be soon ;-> since I had >the similiar experience there!!!Uuh!! how my wrists hurt since they are >hanging on the edge of that stupid desk!! I have taken over 30 exams in >my professional career starting with the CNA/CNE 3 way back in 1995 with >no problem in acquiring generous sheets of white paper and plenty of >space to write...But this one??Anyways, the results are going to be >mailed in a couple of weeks. Just prep'd. for a week since someone last >week posted this new exam info. on this site...And as Monday the >31st >was the last day, I decided to take it on Friday (lest I failed and >could retake it on Monday again!!) But since I am going to know the >results in a couple of weeks, I might just chill for now and pray I >passedhopefully I did ;->Anyone else who has taken the exam, any >feedback?Sincerely,CN > > > >The new MSN 8: smart spam protection and 2 months FREE* > > > > misconduct and Nondisclosure violations to [EMAIL PROTECTED] > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66452&t=66432 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP default-originate crashes the router every [7:66269]
Look into Cisco bug ID CSCdp26660. Basically you'll need to either not use the command or upgrade the IOS. Brian Dennis, CCIE #2210 (R&S/ISP-Dial/Security) Director of CCIE Training and Development - IPexpert, Inc. Mailto: [EMAIL PROTECTED] Outside U.S. & Canada: 312.321.6924 URL: http://www.IPexpert.NET "Self-Paced, Instructor Led & Distance Learning (vClass) CCIE Training!" -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Cisco Nuts Sent: Wednesday, March 26, 2003 7:50 AM To: [EMAIL PROTECTED] Subject: BGP default-originate crashes the router everytime - Why?? [7:66258] Hello, Everytime, I configure #nei a.b.c.d default-originate on my routers, it crashes the router. I have tried this on different routers and it's the same result every time. Is this a problem on 25xx's series? My routers have 16Flash and 16Dram. Anyone with a similar experience? Thank you. Sincerely, CN Excerpt from my router: AS1239-A(config-router)#nei 180.80.10.1 default-originate AS1239-A(config-router)# === Flushing messages (21:04:23 UTC Mon Mar 1 1993) === Buffered messages: 00:00:12: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram 00:00:14: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up 00:00:14: %LINK-3-UPDOWN: Interface Serial0, changed state to up 00:00:14: %LINK-3-UPDOWN: Interface Serial1, changed state to down 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to up 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up 00:01:54: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to up 00:01:56: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up 00:02:01: %LINK-5-CHANGED: Interface Serial1, changed state to administratively down 00:02:02: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, changed state to down 00:02:02: %SYS-5-CONFIG_I: Configured from memory by console 00:02:50: %SYS-5-RESTART: System restarted -- Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1), RELEASE SOFTWARE (fc2) Copyright (c) 1986-2001 by cisco Systems, Inc. Compiled Fri 27-Apr-01 15:20 by cmong 00:03:10: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up 01:20:21: %SYS-5-CONFIG_I: Configured from console by console 01:50:45: %SYS-5-CONFIG_I: Configured from console by console 19:09:35: %SYS-5-CONFIG_I: Configured from console by console 19:12:12: %BGP-5-ADJCHANGE: neighbor 160.60.10.1 Up 19:30:06: %SYS-5-CONFIG_I: Configured from console by console 19:52:26: %SYS-5-CONFIG_I: Configured from console by console 20:02:48: %SYS-5-CONFIG_I: Configured from console by console 20:11:47: %SYS-5-CONFIG_I: Configured from console by console 20:35:37: %SYS-5-CONFIG_I: Configured from console by console 20:44:02: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap 20:44:02: %SYS-5-CONFIG_I: Configured from console by console 20:44:04: %LINK-5-CHANGED: Interface Ethernet0, changed state to administratively down 20:44:05: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to down 20:49:20: %SYS-5-CONFIG_I: Configured from console by console 20:49:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up 20:49:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to up 20:49:30: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up 21:00:44: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap 21:00:45: %SYS-5-CONFIG_I: Configured from console by console 21:00:46: %LINK-5-CHANGED: Interface Ethernet0, changed state to administratively down 21:00:47: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to down 21:01:19: %SYS-5-CONFIG_I: Configured from console by console 21:01:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up 21:01:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to up 21:01:47: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up Queued messages: Exception: Illegal Instruction at 0x0 (PC) System Bootstrap, Version 5.2(8a), RELEASE SOFTWARE Copyright (c) 1986-1995 by cisco Systems 2500 processor with 14336 Kbytes of main memory F3: 15343148+1154396+1180856 at 0x360 Restricted Rights Legend Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) of the Commercial Computer Software - Restricted Rights clause at FAR sec. 52.227-19 and subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS sec. 252.227-7013. cisco Systems, Inc. 170 West Tasman Drive San Jose, California 95134-1706 Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1), RELEASE SOFTWARE (fc2) Copyright (c) 1986-2001 by cisco Systems, Inc. Compiled Fri 27-Apr-01 15:20 by cmong Image text-base: 0x0307EE08, data-base: 0x1000 Compliance with U.S. E
Re: BGP default-originate crashes the router everytime - Why?? [7:66322]
I have 12.2.1 Enterprise Plus.I looked at the Bug info. on CCO and this one is not listedMaybe Cisco was still not out with this ver. at that time My ver: flash:c2500-jk8os-l.122-1.bin Looks like then 12.2.12a Enterprise is what I need!! Thank you. >From: "The Long and Winding Road" >Reply-To: "The Long and Winding Road" >To: [EMAIL PROTECTED] >Subject: Re: BGP default-originate crashes the router everytime - Why?? >[7:66274] >Date: Wed, 26 Mar 2003 19:47:25 GMT > >""Cisco Nuts"" wrote in message >news:[EMAIL PROTECTED] > > Hello, > > Everytime, I configure #nei a.b.c.d default-originate on my routers, it > > crashes the router. I have tried this on different routers and it's the > > same result every time. Is this a problem on 25xx's series? My routers >have > > 16Flash and 16Dram. > > Anyone with a similar experience? > > >this is a known bug with several versions of IOS 12.1. the answer is to >upgrade - or never issue the command > >12.1.5Tx seems to be stable. >12.2.12a seems to be OK > >when I ran into this a year or so ago I had to upgrade from 12.1.2 to >something like 12.1.10. As I said - the T train seems to be stable also. > > > > > > Thank you. > > Sincerely, > > CN > > > > Excerpt from my router: > > > > AS1239-A(config-router)#nei 180.80.10.1 default-originate > > AS1239-A(config-router)# > > > > === Flushing messages (21:04:23 UTC Mon Mar 1 1993) === > > > > Buffered messages: > > > > 00:00:12: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram > > 00:00:14: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > > 00:00:14: %LINK-3-UPDOWN: Interface Serial0, changed state to up > > 00:00:14: %LINK-3-UPDOWN: Interface Serial1, changed state to down > > 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, >changed > > state to up > > 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed > > state to up > > 00:01:54: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, >changed > > state to up > > 00:01:56: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed > > state to up > > 00:02:01: %LINK-5-CHANGED: Interface Serial1, changed state to > > administratively down > > 00:02:02: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, >changed > > state to down > > 00:02:02: %SYS-5-CONFIG_I: Configured from memory by console > > 00:02:50: %SYS-5-RESTART: System restarted -- > > Cisco Internetwork Operating System Software > > IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1), RELEASE >SOFTWARE > > (fc2) > > Copyright (c) 1986-2001 by cisco Systems, Inc. > > Compiled Fri 27-Apr-01 15:20 by cmong > > 00:03:10: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up > > 01:20:21: %SYS-5-CONFIG_I: Configured from console by console > > 01:50:45: %SYS-5-CONFIG_I: Configured from console by console > > 19:09:35: %SYS-5-CONFIG_I: Configured from console by console > > 19:12:12: %BGP-5-ADJCHANGE: neighbor 160.60.10.1 Up > > 19:30:06: %SYS-5-CONFIG_I: Configured from console by console > > 19:52:26: %SYS-5-CONFIG_I: Configured from console by console > > 20:02:48: %SYS-5-CONFIG_I: Configured from console by console > > 20:11:47: %SYS-5-CONFIG_I: Configured from console by console > > 20:35:37: %SYS-5-CONFIG_I: Configured from console by console > > 20:44:02: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap > > 20:44:02: %SYS-5-CONFIG_I: Configured from console by console > > 20:44:04: %LINK-5-CHANGED: Interface Ethernet0, changed state to > > administratively down > > 20:44:05: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, >changed > > state to down > > 20:49:20: %SYS-5-CONFIG_I: Configured from console by console > > 20:49:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > > 20:49:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, >changed > > state to up > > 20:49:30: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up > > 21:00:44: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap > > 21:00:45: %SYS-5-CONFIG_I: Configured from console by console > > 21:00:46: %LINK-5-CHANGED: Interface Ethernet0, changed state to > > administratively down > > 21:00:47: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, >changed > > state to down > > 21:01:19: %SYS-5-CONFIG_I: Configured from console by console > > 21:01:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > > 21:01:22: %LINEPROT
Re: BGP default-originate crashes the router everytime - Why?? [7:66274]
""Cisco Nuts"" wrote in message news:[EMAIL PROTECTED] > Hello, > Everytime, I configure #nei a.b.c.d default-originate on my routers, it > crashes the router. I have tried this on different routers and it's the > same result every time. Is this a problem on 25xx's series? My routers have > 16Flash and 16Dram. > Anyone with a similar experience? this is a known bug with several versions of IOS 12.1. the answer is to upgrade - or never issue the command 12.1.5Tx seems to be stable. 12.2.12a seems to be OK when I ran into this a year or so ago I had to upgrade from 12.1.2 to something like 12.1.10. As I said - the T train seems to be stable also. > Thank you. > Sincerely, > CN > > Excerpt from my router: > > AS1239-A(config-router)#nei 180.80.10.1 default-originate > AS1239-A(config-router)# > > === Flushing messages (21:04:23 UTC Mon Mar 1 1993) === > > Buffered messages: > > 00:00:12: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram > 00:00:14: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > 00:00:14: %LINK-3-UPDOWN: Interface Serial0, changed state to up > 00:00:14: %LINK-3-UPDOWN: Interface Serial1, changed state to down > 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to up > 00:00:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed > state to up > 00:01:54: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to up > 00:01:56: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed > state to up > 00:02:01: %LINK-5-CHANGED: Interface Serial1, changed state to > administratively down > 00:02:02: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, changed > state to down > 00:02:02: %SYS-5-CONFIG_I: Configured from memory by console > 00:02:50: %SYS-5-RESTART: System restarted -- > Cisco Internetwork Operating System Software > IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1), RELEASE SOFTWARE > (fc2) > Copyright (c) 1986-2001 by cisco Systems, Inc. > Compiled Fri 27-Apr-01 15:20 by cmong > 00:03:10: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up > 01:20:21: %SYS-5-CONFIG_I: Configured from console by console > 01:50:45: %SYS-5-CONFIG_I: Configured from console by console > 19:09:35: %SYS-5-CONFIG_I: Configured from console by console > 19:12:12: %BGP-5-ADJCHANGE: neighbor 160.60.10.1 Up > 19:30:06: %SYS-5-CONFIG_I: Configured from console by console > 19:52:26: %SYS-5-CONFIG_I: Configured from console by console > 20:02:48: %SYS-5-CONFIG_I: Configured from console by console > 20:11:47: %SYS-5-CONFIG_I: Configured from console by console > 20:35:37: %SYS-5-CONFIG_I: Configured from console by console > 20:44:02: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap > 20:44:02: %SYS-5-CONFIG_I: Configured from console by console > 20:44:04: %LINK-5-CHANGED: Interface Ethernet0, changed state to > administratively down > 20:44:05: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to down > 20:49:20: %SYS-5-CONFIG_I: Configured from console by console > 20:49:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > 20:49:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to up > 20:49:30: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up > 21:00:44: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Down Interface flap > 21:00:45: %SYS-5-CONFIG_I: Configured from console by console > 21:00:46: %LINK-5-CHANGED: Interface Ethernet0, changed state to > administratively down > 21:00:47: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to down > 21:01:19: %SYS-5-CONFIG_I: Configured from console by console > 21:01:21: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up > 21:01:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed > state to up > 21:01:47: %BGP-5-ADJCHANGE: neighbor 180.80.10.1 Up > Queued messages: > Exception: Illegal Instruction at 0x0 (PC) > > System Bootstrap, Version 5.2(8a), RELEASE SOFTWARE > Copyright (c) 1986-1995 by cisco Systems > 2500 processor with 14336 Kbytes of main memory > > F3: 15343148+1154396+1180856 at 0x360 > > Restricted Rights Legend > > Use, duplication, or disclosure by the Government is > subject to restrictions as set forth in subparagraph > (c) of the Commercial Computer Software - Restricted > Rights clause at FAR sec. 52.227-19 and subparagraph > (c) (1) (ii) of the Rights in Technical Data and Computer > Software clause at DFARS sec. 252.227-7013. > >cisco Systems, Inc. >170 West Tasman Drive >San Jose, California 95134-1706 > > > > Cisco Internetwork Operating System Software > IOS (tm) 2500 Software (C2500-JK8OS-L), Version 12.2(1), RELEASE SOFTWARE > (fc2) > Copyright (c) 1986-2001 by cisco Systems, Inc. > Compiled Fri 27-Apr-01 15:20 by cmong > Image text-base: 0x0307EE08, data-base: 0x1000 > > > Compliance with U.S. Export Laws and Regulations - Encryption > > This product performs encryption
RE: BGP Multihome 2 isp's [7:66137]
Well, you are right!! Why even use distribute-lists in the first place? Route-maps are more flexible... He can even match as-path 1 and set the filter-list to ^$. This way, in case he has to advertise networks in the future, he does not need to worry about adding it to the acl. And for outbound, prefix-list/distribute-list takes precedence over a filter-list over a route-map. And since this is 2 different ISP's, I would just load-share the traffic for outbound and inbound... Prepend out one ISP for Inbound and set the wt. in on the other for outbound. Or he can also just set 2 static default routes out with one having a higher AD This way, he does not have to depend on the ISP's for the default - more control. Well, that's just my 2c ;-> >From: "Charles D Hammonds" >Reply-To: "Charles D Hammonds" >To: [EMAIL PROTECTED] >Subject: RE: BGP Multihome 2 isp's [7:66137] >Date: Wed, 26 Mar 2003 01:58:49 GMT > >didn't even look at your config the first time 'round, but now that I do... > >if you're using distribute-lists, why match ip addr again in route-map >6128? >remove the match clause and just set as-path prepend (if you must) since >you >only have the one route. then you can get rid of access-list 30 > >charles > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of >Charles D Hammonds >Sent: Tuesday, March 25, 2003 4:28 PM >To: [EMAIL PROTECTED] >Subject: RE: BGP Multihome 2 isp's [7:66137] > > >that would work, but I would get at least each providers internal routes >rather than just a default. and unless it's for financial reasons (i.e. >billed per usage) I wouldn't prepend your AS on either link... just let the >internet do its thing and choose the best path. > >Charles > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of J >M >Sent: Tuesday, March 25, 2003 3:21 AM >To: [EMAIL PROTECTED] >Subject: BGP Multihome 2 isp's [7:66137] > > >we are multihomed to 2 isp's on 1 router I only want to send the one >network >62.154.91.0 > >and only want to recieve the default 0.0.0.0 >addit9onally i want to prepend our as 23484 outbound to 1 neighbor >does this work? > >is there a better way? > > > > > > >router bgp 23484 > no synchronization > bgp log-neighbor-changes > network 62.154.91.0 mask 255.255.255.0 > neighbor 146.223.74.37 remote-as 1239 > neighbor 146.223.74.37 distribute-list 20 in > neighbor 146.223.74.37 distribute-list 10 out > neighbor 162.206.236.69 remote-as 6128 > neighbor 162.206.236.69 distribute-list 20 in > neighbor 162.206.236.69 distribute-list 10 out > neighbor 162.206.236.69 route-map 6128 out > no auto-summary >! >ip classless >no ip http server >ip http access-class 1 >! >access-list 10 permit 62.154.91.0 0.0.0.255 >access-list 20 permit 0.0.0.0 log >access-list 30 permit 62.154.91.0 0.0.0.255 > > >route-map 6128 permit 30 > match ip address 30 > set as-path prepend 23484 >! _ Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66250&t=66137 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Multihome 2 isp's [7:66137]
didn't even look at your config the first time 'round, but now that I do... if you're using distribute-lists, why match ip addr again in route-map 6128? remove the match clause and just set as-path prepend (if you must) since you only have the one route. then you can get rid of access-list 30 charles -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Charles D Hammonds Sent: Tuesday, March 25, 2003 4:28 PM To: [EMAIL PROTECTED] Subject: RE: BGP Multihome 2 isp's [7:66137] that would work, but I would get at least each providers internal routes rather than just a default. and unless it's for financial reasons (i.e. billed per usage) I wouldn't prepend your AS on either link... just let the internet do its thing and choose the best path. Charles -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of J M Sent: Tuesday, March 25, 2003 3:21 AM To: [EMAIL PROTECTED] Subject: BGP Multihome 2 isp's [7:66137] we are multihomed to 2 isp's on 1 router I only want to send the one network 62.154.91.0 and only want to recieve the default 0.0.0.0 addit9onally i want to prepend our as 23484 outbound to 1 neighbor does this work? is there a better way? router bgp 23484 no synchronization bgp log-neighbor-changes network 62.154.91.0 mask 255.255.255.0 neighbor 146.223.74.37 remote-as 1239 neighbor 146.223.74.37 distribute-list 20 in neighbor 146.223.74.37 distribute-list 10 out neighbor 162.206.236.69 remote-as 6128 neighbor 162.206.236.69 distribute-list 20 in neighbor 162.206.236.69 distribute-list 10 out neighbor 162.206.236.69 route-map 6128 out no auto-summary ! ip classless no ip http server ip http access-class 1 ! access-list 10 permit 62.154.91.0 0.0.0.255 access-list 20 permit 0.0.0.0 log access-list 30 permit 62.154.91.0 0.0.0.255 route-map 6128 permit 30 match ip address 30 set as-path prepend 23484 ! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66219&t=66137 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP Multihome 2 isp's [7:66137]
that would work, but I would get at least each providers internal routes rather than just a default. and unless it's for financial reasons (i.e. billed per usage) I wouldn't prepend your AS on either link... just let the internet do its thing and choose the best path. Charles -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of J M Sent: Tuesday, March 25, 2003 3:21 AM To: [EMAIL PROTECTED] Subject: BGP Multihome 2 isp's [7:66137] we are multihomed to 2 isp's on 1 router I only want to send the one network 62.154.91.0 and only want to recieve the default 0.0.0.0 addit9onally i want to prepend our as 23484 outbound to 1 neighbor does this work? is there a better way? router bgp 23484 no synchronization bgp log-neighbor-changes network 62.154.91.0 mask 255.255.255.0 neighbor 146.223.74.37 remote-as 1239 neighbor 146.223.74.37 distribute-list 20 in neighbor 146.223.74.37 distribute-list 10 out neighbor 162.206.236.69 remote-as 6128 neighbor 162.206.236.69 distribute-list 20 in neighbor 162.206.236.69 distribute-list 10 out neighbor 162.206.236.69 route-map 6128 out no auto-summary ! ip classless no ip http server ip http access-class 1 ! access-list 10 permit 62.154.91.0 0.0.0.255 access-list 20 permit 0.0.0.0 log access-list 30 permit 62.154.91.0 0.0.0.255 route-map 6128 permit 30 match ip address 30 set as-path prepend 23484 ! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66213&t=66137 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP bestpath as-path ignore - Hidden cmd?? [7:65987]
""Cisco Nuts"" wrote in message news:[EMAIL PROTECTED] > Hello, > Why is BGP bestpath as-path ignore a hidden cmd - if it indeed is?? Here is > what I got: > AS7018-NAP(config)#router bgp 7018 > AS7018-NAP(config-router)#bgp bestpath as? > % Unrecognized command > AS7018-NAP(config-router)#bgp bestpath as-path ? > % Unrecognized command > AS7018-NAP(config-router)#bgp bestpath as-path ignore > AS7018-NAP(config-router)# > > AS7018-NAP#rbr > router bgp 7018 > no synchronization > bgp router-id 150.50.100.100 > bgp log-neighbor-changes > bgp bestpath as-path ignore > > > Any ideas?? I've been going through the Parkhurt book again, and I have found a couple of these kinds of things on the IOS images I am using. IOS 12.1.5T10 and 12.2.12a. I believe both of these are IP Plus. neighbor x.x.x.x filter-list x weight is not in either of those versions, even though Parkhurst uses the command on page 173 and 174 I suspect these commands are available on higher end equipment. I'm pretty sure Parkhurst was not using 2501's when he did his work. I'm sure he had access to at least 7204's or 6's. > > > > > _ > Help STOP SPAM with the new MSN 8 and get 2 months FREE* > http://join.msn.com/?page=features/junkmail Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65996&t=65987 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP update-source Loopback0 [7:65902]
Not necessarily. Recall that with eBGP sessions it is typical to peer with the physical address. There are times when you want to use the lo0 for eBGP (two parallel links, etc.) but you'll need to specify both ebgp_multihop and define a route to the peer's loopback. Priscilla Oppenheimer wrote: > > What's with the "update-source Loopback0" that you see popping up in BGP > examples in books and white papers with no explanation? :-) What does it mean? > > For example > > router bgp 75 > neighbor 10.100.65.1 remote-as 50 > neighbor 10.100.65.1 update-source Loopback0 > > The example I'm looking at is much more complicated and I can tell you more > if you need me to, but I don't know if the rest of the stuff is relevant to > my question about this "update-source" parameter. > > Wouldn't the router use the Loopback anyway for sending BGP messages? > > Thanks > > Priscilla Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65984&t=65902 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP update-source Loopback0 [7:65902]
"You only have to use the update-source command when someone is peering to your loopback address. This is true for an iBGP peer and an eBGP peer." More info here: http://www.cisco.com/en/US/partner/tech/tk826/tk365/technologies_tech_note09186a0080093fb8.shtml#updatesource Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65908&t=65902 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP dampening [7:65086]
At 07:39 PM 3/11/2003 +, Oliver Hensel wrote: >Hi! > >Can someone point me to a document which explains >what happens with a prefix that is dampened if >it's distributed via two providers. Hi Oliver, Here is a link to a doc from Randy Bush that covers damping in some detail. http://psg.com/~randy/021028.zmao-nanog.pdf (handily posted to NANOG today :) For technical info on damping in general, check rfc 2439, and RIPE 229 for recent best practise config settings (which are put into serious question by the above PDF) Damping was brought into existence as a means to protect routers which could be overwhelmed by a large amount of BGP updates to the extent where they would would either crash, or drop BGP sessions themselves thereby exacerbating the route churn issue. At present, newer routers and better BGP implementations are able to deal with large amounts of BGP updates without any impact to other processes in the router and thus the need to protect them via damping isn't a huge priority. Further, as Randy points out, damping may do more harm than good to route convergence in the global Internet. As a result, I think it is safe to say that the need for damping in general is in serious question. >Will only the penalized route dampened, that is >will we still have connectivity if one link is >flapping. I think so, but I'd like to have some >confirmation for that. BGP prefixes (NLRI) are damped individually, however damping really only impacts you on more remote AS's. In your case, you have a situation like the below: you / \ transit1transit2 | \ / | remote1 - - remote2 | \ / | remote3 --- remote4 When you advertise 10/8 to transit1 and transit2, assuming these folks are clueful and automatically pref customer routes above peer/transit, both of them will always prefer the direct route to you. This is important as implicit withdrawals are penalized in the same way as direct withdrawals. This fact, coupled with the fact that damping stats are cleared on EBGP sessions when the peer resets will tend to make damping irrelevant between neighboring AS's. However, as you get more and more remote, things get worse. To expand on this, consider remote3. Assuming you advertise 10/8 to both transits, imagine that the update from transit2 gets to remote1 first and on to remote3. In this case, remote3 hits you with an advert penalty and posts the route 10/8 via as-path "r1,t2, you" Shortly thereafter, the update from transit1 shows up in remote1 and by virtue of a better AS-PATH becomes the best path in remote1. Remote1 therefore sends an update with the new path info to remote3. This update includes an implicit withdrawal of the old path and a subsequent damping penalty applied to 10/8 in remote3.Likely these two updates appeared in remote 3 in a pretty narrow time window and thus you have a 10/8 prefix that has suffered a nice penalty without ever really flapping. Consider also that depending on AS size, router types, BGP advertisement intervals and such, remote 3 may have seen an r1,r4,r2,t2 path first, then an r1.r2,t2, then an r1,t1 path and may have penalized you once for the initial advert and two more times for the implicit withdrawals which might get you damped in remote3 right off the bat. This issue gets worse as you consider ASes more and more remote from you. For what it's worth, I may have this entirely wrong :-) But this is my understanding of the behavior. The networks I have designed used graded damping and are not tremendously aggressive. I am however considering removing damping from the configs for the few networks I have some impact in as I really don't see it serving much of a role. Pete >Thanks and best regards, > >Oliver > > >-- >Oliver Hensel >telematis Netzwerke GmbH >mailto: [EMAIL PROTECTED] >Siemensstrasse 23, D-76275 Ettlingen >Tel: +49 (0) 7243-3448-0, Fax: -498 >visit us: http://telematis.com >3 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65302&t=65086 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP dampening [7:65086]
At 3:19 AM + 3/12/03, Priscilla Oppenheimer wrote: >I'll take a stab at it since nobody else did. > >Oliver Hensel wrote: >> >> Hi! >> >> Can someone point me to a document which explains >> what happens with a prefix that is dampened if >> it's distributed via two providers. > >I don't think you'll find a document that answers the question explicitly >because the implicit answer is sort of obvious, as I think you realize. > >It's a route that's dampened, not a prefix. With two providers, in most >cases, there would be two distinct routes to your prefix. A BGP route has >path attributes including an AS_Path, which is a list of Autonomous System >numbers. With two providers, the two routes will be distinct and have a >different set of AS numbers in most situations. Otherwise what would be the >point? Depending on how deeply you want to go, there is a very nuanced range of ideas in BGP information and how it is propagated. In our http://www.ietf.org/internet-drafts/draft-ietf-bmwg-conterm-04.txt , there was tremendous effort to clarify, and part of this clarification means that you probably have to understand the differences among a dozen or so seemingly alike concepts. These are also being refined in the new BGP standard, which is at draft 19 when last I looked -- and probably still has a round or two to go. Let's put it this way...we ducked going deeply into route flaps, much less dampening (an important difference -- they are NOT equivalent) in this version of the document. There are concepts that need to be most thoroughly internalized -- grokked if you will -- before dealing with flap control and propagation. Quite a bit of theoretical analysis is available, but the associated global scalability issues are by no means solved. > >> >> Will only the penalized route dampened, that is >> will we still have connectivity if one link is >> flapping. I think so, but I'd like to have some >> confirmation for that. > >If just one of your links is flapping, then just one of your routes will get >dampened. The other one will still be usable. > >If your two links share a circuit to the telco or physically share a path >that has been dug up by the proverbial back-hoe operator, it's possible both >links could be flapping, and then they will both get dampened, but hopefully >you have a network design that avoids that problem. Don't let BGP rain on >your parade and dampen too much at once! Have good physical diversity. ;-) > >Priscilla > >> >> Thanks and best regards, >> >> Oliver >> >> >> -- >> Oliver Hensel >> telematis Netzwerke GmbH >> mailto:[EMAIL PROTECTED] >> Siemensstrasse 23, D-76275 Ettlingen >> Tel: +49 (0) 7243-3448-0, Fax: -498 >> visit us: http://telematis.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65126&t=65086 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP dampening [7:65086]
I'll take a stab at it since nobody else did. Oliver Hensel wrote: > > Hi! > > Can someone point me to a document which explains > what happens with a prefix that is dampened if > it's distributed via two providers. I don't think you'll find a document that answers the question explicitly because the implicit answer is sort of obvious, as I think you realize. It's a route that's dampened, not a prefix. With two providers, in most cases, there would be two distinct routes to your prefix. A BGP route has path attributes including an AS_Path, which is a list of Autonomous System numbers. With two providers, the two routes will be distinct and have a different set of AS numbers in most situations. Otherwise what would be the point? > > Will only the penalized route dampened, that is > will we still have connectivity if one link is > flapping. I think so, but I'd like to have some > confirmation for that. If just one of your links is flapping, then just one of your routes will get dampened. The other one will still be usable. If your two links share a circuit to the telco or physically share a path that has been dug up by the proverbial back-hoe operator, it's possible both links could be flapping, and then they will both get dampened, but hopefully you have a network design that avoids that problem. Don't let BGP rain on your parade and dampen too much at once! Have good physical diversity. ;-) Priscilla > > Thanks and best regards, > > Oliver > > > -- > Oliver Hensel > telematis Netzwerke GmbH > mailto:[EMAIL PROTECTED] >Siemensstrasse 23, D-76275 Ettlingen >Tel: +49 (0) 7243-3448-0, Fax: -498 > visit us: http://telematis.com > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65120&t=65086 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP notification message [7:63847]
>From the cisco website Error Message %BGP-5-ADJCHANGE: neighbor [chars][chars][chars][chars] [chars] Explanation A BGP neighbor has either come up or gone down. This message describes the change for the BGP neighbor and appears only if the log-neighbor-changes command is configured for the BGP process. Recommended Action This informational message normally appears as routers and BGP neighbors go up or down. However, unexpected neighbor loss might indicate high error rates or high packet loss in the network and should be investigated. Error Message %BGP-6-ASPATH: [chars] AS path [chars] received from [chars]: [chars] Explanation The remote BGP peer has sent in an update with an invalid AS path. Recommended Action Copy the error message exactly as it appears on the console or in the system log, contact your Cisco technical support representative, and provide the representative with the gathered information. Error Message %BGP-3-BADROUTEMAP: Bad parameters in the route-map [chars] applied for [chars] Explanation The route map contains parameters that are incompatible with the intended operation. Recommended Action Correct the route map definition. Error Message %BGP-3-BGP_INCONSISTENT: [chars] Inconsistent [chars] Explanation An inconsistency in the data structures has been detected. Recommended Action This is a rare situation and is the result of an internal problem. Copy the error message exactly as it appears on the console or in the system log, contact your Cisco technical support representative, and provide the representative with the gathered information. Error Message %BGP-3-DELPATH: Attempted to delete path from an empty net for [chars] Explanation A BGP path could not be deleted because of an error. Recommended Action Copy the error message exactly as it appears on the console or in the system log, contact your Cisco technical support representative, and provide the representative with the gathered information. KW S wrote: > > This is the extract from a show log > > Feb 26 03:37:28: %BGP-3-NOTIFICATION: received from neighbor > 203.162.129.39 4/0 (hold time expired) 0 bytes > > Feb 26 03:37:28: %BGP-5-ADJCHANGE: neighbor 203.162.129.39 Down > BGP Notification received > > Feb 26 03:46:44: %BGP-5-ADJCHANGE: neighbor 203.162.129.39 Up > > 1. what is the meaning of BGP-3-notification > 2. what is the meaning of BGP-5-adjchange > 3. Is there a way to tell what is the error code in this > notification message ? > > Can anyone explain the above to me > > Thanks a lot > > kws > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=63851&t=63847 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP notification message [7:63847]
Hi Fred Thanks for your reply. I am trying to find out what causes the peer to lose connection. By looking at the log,I only know that it was down for 9 mins. No other information is given in the log. I know that the notifications message itself has some kind of error code and sub code that will indicate what is the error for eg error code of 1 refers to message header error error code of 2 refers to open message error error code of 3 refers to update message and so on Is there a way where you can see what is the error code in the notification message ? maybe like doing a debug or something ? Regards kws Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=63850&t=63847 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP notification message [7:63847]
Notification is one of the 4 message types used by BGP. The other three are keepalives, open and updates. Notifications are used to inform the receiving router of errors. Looks like neighbor did not respond before hold down time expired and therefore adjacency was lost and then recovered 9 min 16 sec later. Hope this helps. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=63849&t=63847 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Question [7:62914]
Jim, Continue to announce the /19 as before. You MAY want to also announce the /24 you've allocated to your downstream; depending upon the business relationship around this connectivity you may really want to announce the more specific /24. This is probably the critical choice you'll make. More details about the desired function of this interconnection would be needed to make intelligent comments on that. Depending upon the specifics of the environment...The covering /19 will attract some traffic for this /24 regardless of the customer announcing the /24 via other providers. If you also propagate the announcement of this /24 then you will get a bigger % of the inbound traffic for this /24 depending upon the announcements made on the other interconnection(s) the customer AS has. Againmore specifics on the desired traffic flow would be helpful in deciding behaviour in various states. For some example of this When you give backup connectivity to a company which has sublet space from your shrinking dotcom, you'd not like to carry any of this downstream's traffic unless you have to. When you are billing the customer by the bit you'd like to bill them for as much traffic as you can carry without increasing your own costs enough to hurt your margins on the service. Suggestions: -Filter his announcements to you beyond just the as-path filter you've mentioned. Also use prefix list or such to limit the announcements you'll listen to be just the prefixes you've agreed to accept. This is probably just the /24(and nothing longer) you are allocating to him now. -Make sure you are allowing all your routers(especially border) to see this /24(or some covering aggregate) so that you don't create blackholes for some subset of the network. -Adjust your outbound route filters to permit the one /24(and nothing longer) to leak if you've decided you wanted this announced to the world via your network. This probably will require you to speak with your upstreams for them to adjust route filters on their side. -Regardless verify the announcements from outside your network by using a public looking glass. It is likely that all of the objectives for this interconnection will not be met with canned configuration or suggestions. It's also quite common that no one will notice that the objectives are failing to be met. This is usually due to the fact that "it works" right now and "it works" under simple failure modes. Best of luck and if you've got the time to share more details about what is desired the group can make more suggestions, Darrell Newcomb darrell(at)hayaitacosnet http://www.hayaitacos.net/mpeer/ Home of the Managed Peering Service ""Jim Devane"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hi all, > I am looking for some guidelines and I cannot find any relevant examples. I > have a situation where I have SWIP'd a /24 of my address block to a customer > downstream. They have their own AS and are multi-homed. > > My concern/question is: the /24 will originate from their AS and not mine. > Is there any special concerns I will need to take into accoutn for BGP > advertisements to my upstream providers? That is, I will peer with him and > allow his AS to originate the router and allow ^$ from him, but I am > concerned that this will mess up my advertisements of a /19. (the /24 I gave > him is out of my larger. Can I no longer advertise that? > > Are my concerns founded at all? Any advice? > > thanks, > Jim Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62918&t=62914 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP config question. [7:62860]
Pete Thanks for your help. I know it doesnt buy much redundancy, however it is something that could be done to an existing system without much capital outlay, and the organisation that I was thinking of has seemed to have had a run of bad luck with single routers falling over during the last few months. I know the org would prefer to rely on the dual providers for uplink redundancy rather than adding additional redundant links to any single provider. I dont even know if the upstream provider would allow it, but it was just something that occured to me while reading up for the BGP exam I am taking this week and I couldnt really find any answers in my study materials. Yet again, thanks Peter --On 12 February 2003 16:28 + Peter van Oene wrote: > At 03:59 PM 2/12/2003 +, Peter Walker wrote: >> Yep you are right. >> >> Lets try that again ... >> >>a) connect up1 to the same ethernet segment >>b) form bgp neighbor relationship with BGP peer at provider pr2 >>c) advertise appropriate MED values requesting that pr2 prefer >> up2 >> d) set local preference to prefer link via up2 to pr2 over >> up1 to pr2 >> >> In terms of what I am asking is, are there any issues with having two >> 'redundant' bgp links from two different routers in one AS over a single >> multi-access link to a single router in another AS. > > So basically you have two routers and both r1 and r2 connect to the same > router on the provider side while r1 also maintains a connection to > another router on the provider side. In this case, you don't really > buy yourself much other than router redundancy on your side. The cost > is purely in control traffic that will transit the ethernet link. BGP > isn't that chatty unless peering sessions are flapping (which would be > abnormal) so this shouldn't be a big problem. Only other cost would be > additional config complexity which might impede troubleshooting. Beyond > that, things should work fine as long as the provider agrees to set it > up. > > Pete > > > > >> It seems to me that this would be a simple no-brainer type of change to >> make, but I just have a nagging suspicion that there is some gotcha >> waiting to jump out when you least expect it. None of the sample >> configurations I have seen seem to mention this sort of config and I was >> wondering if there was some reason why it shouldnt be done, or if it was >> just one of those obscure variations of common configurations that did >> not warrant it's own explicit mention. >> >> Peter >> >> --On 12 February 2003 14:27 + Peter van Oene wrote: >> >>> At 01:36 PM 2/12/2003 +, Peter Walker wrote: Folks A quick question on external BGP connection configuration. Given an organisation (ORG) with 2 EBGP routers (up1, up2) and two upstream providers (pr1, and pr2) where provider pr1 is currently linked to the router up1 via a serial link and provider pr2 is currently linked to router up2 via a traffic shaped and limited ethernet link. ORG is does not allow transit between the providers. Is there any reason why ORG should not a) connect pr1 to the same ethernet segment b) form bgp neighbor relationship with BGP peer at provider pr2 c) advertise appropriate MED values requesting that pr2 prefer up2 d) set local preference to prefer link via up2 to pr2 over up1 to >>> pr2 >>> >>> >>> I'm not sure if you are messing up your prs and ups here, but I'm not >>> following you entirely. Why would you not just peer both routers and use >>> prepend/med and pref to control load like most folks do? Maybe >>> explaining what is better or different about this approach would help >>> explain what the approach is :) >>> >>> Pete >>> >>> >>> >>> >>> What I am looking for is technical (or business/political) reasons why this is a good or bad idea. I understand that all this would give is redundancy at the router level (up1, up2), the ethernet link and pr2's router are all still potential single points of failure. I also understand that pr2 may not wish to allow such a configuration. Also, what would need to be done to ensure that any changes made would not have any impact on decisions regarding the routing choice between pr1 and pr2? Regards Peter >>> Nondisclosure violations to [EMAIL PROTECTED] > Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62885&t=62860 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP config question. [7:62860]
At 03:59 PM 2/12/2003 +, Peter Walker wrote: >Yep you are right. > >Lets try that again ... > >a) connect up1 to the same ethernet segment >b) form bgp neighbor relationship with BGP peer at provider pr2 >c) advertise appropriate MED values requesting that pr2 prefer > up2 > d) set local preference to prefer link via up2 to pr2 over > up1 to pr2 > >In terms of what I am asking is, are there any issues with having two >'redundant' bgp links from two different routers in one AS over a single >multi-access link to a single router in another AS. So basically you have two routers and both r1 and r2 connect to the same router on the provider side while r1 also maintains a connection to another router on the provider side. In this case, you don't really buy yourself much other than router redundancy on your side. The cost is purely in control traffic that will transit the ethernet link. BGP isn't that chatty unless peering sessions are flapping (which would be abnormal) so this shouldn't be a big problem. Only other cost would be additional config complexity which might impede troubleshooting. Beyond that, things should work fine as long as the provider agrees to set it up. Pete >It seems to me that this would be a simple no-brainer type of change to >make, but I just have a nagging suspicion that there is some gotcha >waiting to jump out when you least expect it. None of the sample >configurations I have seen seem to mention this sort of config and I was >wondering if there was some reason why it shouldnt be done, or if it was >just one of those obscure variations of common configurations that did not >warrant it's own explicit mention. > >Peter > >--On 12 February 2003 14:27 + Peter van Oene wrote: > >>At 01:36 PM 2/12/2003 +, Peter Walker wrote: >>>Folks >>> >>>A quick question on external BGP connection configuration. >>> >>>Given an organisation (ORG) with 2 EBGP routers (up1, up2) and two >>>upstream providers (pr1, and pr2) where provider pr1 is currently linked >>>to the router up1 via a serial link and provider pr2 is currently linked >>>to router up2 via a traffic shaped and limited ethernet link. ORG is >>>does not allow transit between the providers. >>> >>>Is there any reason why ORG should not >>> >>> a) connect pr1 to the same ethernet segment >>> b) form bgp neighbor relationship with BGP peer at provider pr2 >>> c) advertise appropriate MED values requesting that pr2 prefer >>> up2 d) set local preference to prefer link via up2 to pr2 over >>> up1 to >>pr2 >> >> >>I'm not sure if you are messing up your prs and ups here, but I'm not >>following you entirely. Why would you not just peer both routers and use >>prepend/med and pref to control load like most folks do? Maybe explaining >>what is better or different about this approach would help explain what >>the approach is :) >> >>Pete >> >> >> >> >> >>>What I am looking for is technical (or business/political) reasons why >>>this is a good or bad idea. >>> >>>I understand that all this would give is redundancy at the router level >>>(up1, up2), the ethernet link and pr2's router are all still potential >>>single points of failure. I also understand that pr2 may not wish to >>>allow such a configuration. >>> >>>Also, what would need to be done to ensure that any changes made would >>>not have any impact on decisions regarding the routing choice between >>>pr1 and pr2? >>> >>>Regards >>> >>> Peter >>Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62878&t=62860 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP config question. [7:62860]
Yep you are right. Lets try that again ... a) connect up1 to the same ethernet segment b) form bgp neighbor relationship with BGP peer at provider pr2 c) advertise appropriate MED values requesting that pr2 prefer up2 d) set local preference to prefer link via up2 to pr2 over up1 to pr2 In terms of what I am asking is, are there any issues with having two 'redundant' bgp links from two different routers in one AS over a single multi-access link to a single router in another AS. It seems to me that this would be a simple no-brainer type of change to make, but I just have a nagging suspicion that there is some gotcha waiting to jump out when you least expect it. None of the sample configurations I have seen seem to mention this sort of config and I was wondering if there was some reason why it shouldnt be done, or if it was just one of those obscure variations of common configurations that did not warrant it's own explicit mention. Peter --On 12 February 2003 14:27 + Peter van Oene wrote: > At 01:36 PM 2/12/2003 +, Peter Walker wrote: >> Folks >> >> A quick question on external BGP connection configuration. >> >> Given an organisation (ORG) with 2 EBGP routers (up1, up2) and two >> upstream providers (pr1, and pr2) where provider pr1 is currently linked >> to the router up1 via a serial link and provider pr2 is currently linked >> to router up2 via a traffic shaped and limited ethernet link. ORG is >> does not allow transit between the providers. >> >> Is there any reason why ORG should not >> >> a) connect pr1 to the same ethernet segment >> b) form bgp neighbor relationship with BGP peer at provider pr2 >> c) advertise appropriate MED values requesting that pr2 prefer >> up2 d) set local preference to prefer link via up2 to pr2 over >> up1 to > pr2 > > > I'm not sure if you are messing up your prs and ups here, but I'm not > following you entirely. Why would you not just peer both routers and use > prepend/med and pref to control load like most folks do? Maybe explaining > what is better or different about this approach would help explain what > the approach is :) > > Pete > > > > > >> What I am looking for is technical (or business/political) reasons why >> this is a good or bad idea. >> >> I understand that all this would give is redundancy at the router level >> (up1, up2), the ethernet link and pr2's router are all still potential >> single points of failure. I also understand that pr2 may not wish to >> allow such a configuration. >> >> Also, what would need to be done to ensure that any changes made would >> not have any impact on decisions regarding the routing choice between >> pr1 and pr2? >> >> Regards >> >> Peter > Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62875&t=62860 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP config question. [7:62860]
At 01:36 PM 2/12/2003 +, Peter Walker wrote: >Folks > >A quick question on external BGP connection configuration. > >Given an organisation (ORG) with 2 EBGP routers (up1, up2) and two upstream >providers (pr1, and pr2) where provider pr1 is currently linked to the >router up1 via a serial link and provider pr2 is currently linked to router >up2 via a traffic shaped and limited ethernet link. ORG is does not allow >transit between the providers. > >Is there any reason why ORG should not > > a) connect pr1 to the same ethernet segment > b) form bgp neighbor relationship with BGP peer at provider pr2 > c) advertise appropriate MED values requesting that pr2 prefer up2 > d) set local preference to prefer link via up2 to pr2 over up1 to pr2 I'm not sure if you are messing up your prs and ups here, but I'm not following you entirely. Why would you not just peer both routers and use prepend/med and pref to control load like most folks do? Maybe explaining what is better or different about this approach would help explain what the approach is :) Pete >What I am looking for is technical (or business/political) reasons why this >is a good or bad idea. > >I understand that all this would give is redundancy at the router level >(up1, up2), the ethernet link and pr2's router are all still potential >single points of failure. I also understand that pr2 may not wish to allow >such a configuration. > >Also, what would need to be done to ensure that any changes made would not >have any impact on decisions regarding the routing choice between pr1 and >pr2? > >Regards > > Peter Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62864&t=62860 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP exam study recommendations [7:62784]
At 4:11 AM + 2/11/03, Peter van Oene wrote: >At 11:40 PM 2/10/2003 +, Peter Walker wrote: >>Folks >> >>I am wondering if anyone has any recommendations for BGP study. I am >>booked in for the BGP beta exam on Friday and still dont feel >>comfortable with my level of BGP knowledge. I have read the following >>over the last few months >> >> Halabi - Internet Routing Architectures. >> Doyle Vol 2 (BGP sections) >> John Stewart III (BGP4 book) >> William Parkhurst (The RFC stuff at the back >> and some of the command reference) >> >>I am going to go back and reread some of Halabi, all of the Parkhurst >>command reference chapters and probably some of the RFCs. As to the RFCs -- navigate to the IDR Working Group at www.ietf.org, and look at some of the newer documents on BGP. In particular, download the most recent draft of the BGP specification (think it's 18, but might not be). That draft is much closer to industry implementation than RFC 1771. > > >>Does anyone have any additional 'must-read' references that I should >>look at before Friday? I realise that I have all the basic info that I >>need and, to be honest, feel that I could pass the test already. However >>I am one of those people that want to understand things at the >>gut/instinct level and I really dont feel that I am at that point yet. > >If you read all this stuff and still don't understand BGP the way you would >like to, more books likely aren't what you need. I would focus more on >hands on work. Many folks learn better by doing than reading (me for one >:). If you are a Certificationzone subscriber, Howard Berkowitz has a >three tutorial set on BGP that come with some labs to help illustrate >points which might help. But I'm sure just working through some configs on >a lab while following along with your reading material might be the best bet. > BGP didn't truly make sense to me until I studied routing policy. A good starting site for lots of tutorials is www.radb.org. The RFC "Using RPSL in Practice" and the various RPSL tutorials are good starts to understand what you are trying to accomplish with your policy. There's some freeware such as RtConfig on the site, which will translate some routing policy into Cisco config language. It may not support some of the newer features, and you may not have time to set it up by Friday. My Certzone tutorial, of course, is strictly Cisco oriented. I've also written two books, WAN Survival Guide and Building Service Provider Networks, that focus on "what problem are you trying to solve", respectively, from the enterprise and carrier perspective. The latter goes more deeply into BGP case studies, but does not have specific Cisco commands. > > >>Any other suggestions? >> >>Peter Walker >> CISSP, CSS1, CC[NID]P, etc Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62813&t=62784 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP exam study recommendations [7:62784]
At 11:40 PM 2/10/2003 +, Peter Walker wrote: >Folks > >I am wondering if anyone has any recommendations for BGP study. I am >booked in for the BGP beta exam on Friday and still dont feel >comfortable with my level of BGP knowledge. I have read the following >over the last few months > > Halabi - Internet Routing Architectures. > Doyle Vol 2 (BGP sections) > John Stewart III (BGP4 book) > William Parkhurst (The RFC stuff at the back > and some of the command reference) > >I am going to go back and reread some of Halabi, all of the Parkhurst >command reference chapters and probably some of the RFCs. > >Does anyone have any additional 'must-read' references that I should >look at before Friday? I realise that I have all the basic info that I >need and, to be honest, feel that I could pass the test already. However >I am one of those people that want to understand things at the >gut/instinct level and I really dont feel that I am at that point yet. If you read all this stuff and still don't understand BGP the way you would like to, more books likely aren't what you need. I would focus more on hands on work. Many folks learn better by doing than reading (me for one :). If you are a Certificationzone subscriber, Howard Berkowitz has a three tutorial set on BGP that come with some labs to help illustrate points which might help. But I'm sure just working through some configs on a lab while following along with your reading material might be the best bet. Pete >Any other suggestions? > >Peter Walker > CISSP, CSS1, CC[NID]P, etc Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62788&t=62784 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP help needed., [7:62736]
Don't have any gear to test this on, but what if you put a "network 1.1.1.1 mask 255.255.255.255" in your AS 200--AS300 eBGP peer? The route received from AS100 will populate the routing table and thus cause AS200's network statement to be satisfied and thus advertised. This may make 1.1.1.1 to appear, at AS300, to originate from both AS100 and AS200... Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62751&t=62736 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: BGP help needed., [7:62736]
Hello, I have the practise lab I am working on. 3 routers in lab, AS100 --AS200-AS300 I have a loopback 1.1.1.1 in AS100 and I want to advertise it to AS200 who in turn will advertise it to AS300. When it arrives in AS300 it has to look like it originated in AS200 and NOT for AS300. This needs be achieved with 1 command on AS200. Anyone any idea how to do get this to work, Can this be done,..?? Kind regards, Paul. This E-mail is from O2. The E-mail and any files transmitted with it are confidential and may also be privileged and intended solely for the use of the individual or entity to whom they are addressed. Any unauthorised direct or indirect dissemination, distribution or copying of this message and any attachments is strictly prohibited. If you have received the E-mail in error please notify [EMAIL PROTECTED] or telephone ++ 353 1 6095000. * Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62736&t=62736 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP question. [7:62519]
Hi Rajesh, In mail.net.groupstudy.pro, you wrote: > I come across some situations where I could see some routes in the BGP > table, but those routes aren't there in the regular routing table. The > configuration has "no sync" configured and couldn't guess how to go > about it. Can somebody help me out here? Is this an EBGP or IBGP neighbor? If EBGP, is the prefix being dampened? Is the nexthop for the prefix reachable? Is there a route-map being applied inbound? Is there a prefix-list being applied inbound? Is there a distribute-list being applied inbound? Are you using soft-reconfig? Is this a normal AFI IPv4 prefix? Are you using traditional config or NLRIs? Do the routes not imported have something in common? It would help a lot if you pasted sh ip bgp nei addr, sh ip bgp prefix and sh ip ro nexthop. Everybody uses "no synchronization" nowadays, it's a bugwards compatibility feature that you need to turn specify it in your configuration. // kaj Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62527&t=62519 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP question. [7:62519]
Rajesh, Check the next hop for the BGP routes and see if it is reachable. If not you can use next-hop-self command to fix the issue or have IGP reach that next hop address. Hope this helps. Sunil Soporie ""Rajesh Kumar"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hi all, > > I come across some situations where I could see some routes in the BGP > table, but those routes aren't there in the regular routing table. The > configuration has "no sync" configured and couldn't guess how to go > about it. Can somebody help me out here? > > thanks, > r Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62522&t=62519 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: bgp community [7:62326]
Hi Pete, Try clearing the 'set community no-export' command in your route map and see if 22.22.22.22/24 propagates over to 153.153.3.3. I am suspecting maybe tagging the no-export community while redistributing into the bgp process may actually cause the Loopback22 route not to be exported If that works, maybe you may want to try this command as well. 'neighbor 153.153.3.3 route-map out' You can use your 'loops' routemap if you want. Don't forget to issue a 'clear ip bgp 153.153.3.3' command to restart the session. HTH Wes ""Peter Paul"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > can someone help me? i am currently doing bgp in my test lab. i did a > community no-advertise in one of the routes to be advertise by the local as > to another as, but i can't see it in that other as. i also did a > redistribution from bgp to igp (ospf) in the other as so that both bgp and > igp would sync because one of the problems stated that i should not disable > sync. did i missed something? here's my config in my test lab: > > router bgp 2 > bgp log-neighbor-changes > redistribute connected route-map loops > neighbor 153.153.3.3 remote-as 3 > neighbor 153.153.3.3 ebgp-multihop 255 > neighbor 153.153.3.3 update-source Loopback10 > neighbor 153.153.3.3 send-community > > route-map loops permit 10 > match interface Loopback33 Loopback55 > set origin igp > ! > route-map loops permit 20 > match interface Loopback22 - loopback 22 is 22.22.22.22/24 > set origin igp > set community no-export > > when i did show ip bgp on the 153.153.3.3 router, > > Network Next HopMetric LocPrf Weight Path > *>i11.0.0.0 153.153.1.1 100 0 23 111 i > *> 33.0.0.0 153.153.6.6 1 0 2 i > *>i44.0.0.0 153.153.1.1 100 0 23 111 i > *> 55.0.0.0 153.153.6.6 1 0 2 i > *>i66.0.0.0 153.153.1.1 100 0 23 111 777 i > *>i77.0.0.0 153.153.1.1 100 0 23 111 444 555 i > *>i103.103.103.0/24 153.153.1.1 0100 0 23 i > *>i183.0.0.0/8 153.153.4.4 100 0 65003 i > > i can't see the 22.0.0.0 network. thanks in advance. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62327&t=62326 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP beta exam 641-661 [7:62169]
r u sure dre? because BSCI is already testing BGP heavily. It looks like its a new elective or they may make it a required exam in addition to BSCI and MCAST. dre wrote:""Amin Moustafa"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > What about the new BGP beta exam? > will it be a new CCIP elective one? My guess is that Cisco is replacing the MCAST+QOS course with BGP and making it a required part of CCIP certification, not as an elective. -dre Shahid Muhammad Shafi "Every man dies; not every man really lives" remember, if God bringz u 2 it, He WILL bring u thru it!!!- Please help feed hungry people worldwide http://www.hungersite.com/ A small thing each of us can do to help others less fortunate than ourselves - Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62290&t=62169 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP beta exam 641-661 [7:62169]
""Amin Moustafa"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > What about the new BGP beta exam? > will it be a new CCIP elective one? My guess is that Cisco is replacing the MCAST+QOS course with BGP and making it a required part of CCIP certification, not as an elective. -dre Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62198&t=62169 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP beta exam 641-661 [7:62169]
Does this exam count for 1 Certification (CCIP)? ""Amin Moustafa"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hi all > What about the new BGP beta exam? > will it be a new CCIP elective one? > Regards Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62188&t=62169 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP prefix list question [7:62138]
This is a minor detail that a lot of documentation assumes you know already, which is a bad assumption. le = less than or equal to, ge = greater than or equal to. Read the prefix lists in that manner and they suddenly make a lot more sense! HTH, John >>> "ericbrouwers" 1/29/03 2:44:47 PM >>> Hello, I've a question about BGP prefix-lists. In BGP prefix commands the operators "le" and "ge" can be used. For instance: ip prefix-list abc permit 0.0.0.0/0 ge 8 le 24 I suppose that the "e" in "le" and "ge" means "equal to", doesn't it? I ask this because Cisco's prefix-list documentation is sometimes ambiguous with respect to ranges and equations (at least for me as a non-native English speaker): - "from 8 to 24". This includes (both 8 and) 24, doesn't it? - "up to 24". This includes 24, doesn't it? - "greater than 25". In my opinion this does not include 25, but in some prefix-list examples Cisco suggests it is included. - "less than 16". In my opinion this does not include 16, but in some prefix-list examples Cisco suggests it is included. Thanks for any comments. Eric Brouwers Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=62140&t=62138 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP config query with Loopback [7:61756]
I am confused why you are using dafault routes and BGP at the same time in this setup and why you are using IGP with just 2 routers? Coming back to your question: When you advertise an IGP route in the BGP process with "network" statement, the ORIGIN attribute in the update messages is set to IGP (highest preference). This can affect the selection of best path. Second, looks like that Cisco "wieght" is affecting the selection of best path. By default, all Router originated prefixes have a weight of 32768 as in your case, so we can ignore them. Now for the peer advertised routes, looks like your AS number is considered as weight. Since 4799 is higher than default, it also comes as best path, 111 is lower so it does not. It is my guess as I have not configured and tried it. Try changing 111 to some number higher than 32768 and see. Let me know cause I'll be interested to know the outcome. Nadeem == NKP wrote: > Hi , >I have a simple BGP Query , I have got 2 routers : r2 and r5 , which are > connected to each other via serial link and are on different AS , there > routing configs are as follows : > > for r2 : > interface Loopback0 > ip address 202.202.1.1 255.255.255.255 > > router ospf 100 > log-adjacency-changes > network 0.0.0.0 255.255.255.255 area 0 > ! > router bgp 111 > no synchronization > bgp router-id 202.202.1.1 > bgp log-neighbor-changes > network 202.202.1.1 mask 255.255.255.255 > neighbor 101.101.101.77 remote-as 4799 > neighbor 101.101.101.77 ebgp-multihop 5 > neighbor 101.101.101.77 update-source Loopback0 > ! > > and for R5 : > > interface Loopback0 > ip address 101.101.101.77 255.255.255.255 > ! > > router ospf 100 > log-adjacency-changes > network 0.0.0.0 255.255.255.255 area 0 > ! > router bgp 4799 > no synchronization > bgp router-id 101.101.101.77 > bgp log-neighbor-changes > network 101.101.101.77 mask 255.255.255.255 > neighbor 202.202.1.1 remote-as 111 > neighbor 202.202.1.1 ebgp-multihop 5 > neighbor 202.202.1.1 update-source Loopback0 > ! > > when i see there routing tables , this output is as follows : > > on R2 > >Network Next HopMetric LocPrf Weight Path > * 101.101.101.77/32 > 101.101.101.77 0 0 4799 i > *> 202.202.1.1/32 0.0.0.0 0 32768 i > r2# > r2# > > On r5 it is : > > Network Next HopMetric LocPrf Weight Path > *> 101.101.101.77/32 > 0.0.0.0 0 32768 i > *> 202.202.1.1/32 202.202.1.1 0 0 111 i > r5# > > why is the route of : * 101.101.101.77/32 not coming as the best path > with > on R2 as in the table of r5 it is displaying the path of *> > 202.202.1.1/32 as best path , > > I dont want to do redistribution of BGP in OSPF and plus I dont want to give > any static routes to the peers , as they are getting the path of destination > loopback is known via OSPF , and the routes are there in the routing table FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
