Re: Cannot browse Some Website: Try this: www.sitemeter.com [7:2403]
Can you telnet to port 80 on www.sitemeter.com? This will help you determine if their are filtering issues. Also, try large packet pings with DF set just to verify there are no Path MTU Discovery issues. --trey Ken Yeo wrote: > More info on this: > > When we by pass PIX (plus in a laptop to a hub between PIX and Internet > router). We CAN browse www.sitemeter.com. > > Behind PIX, we can ping www.sitemeter.com and get 100% reply from > 216.167.17.2. But we CANNOT browse using IE. > > Route is going to the correct gateway, do not have 216.167.17 in our WAN. > > So HTTP/application layer coming from the site is definately blocked in the > PIX. > > Any ideas? > > Thanks! > > Ken Yeo > Network Engineer > Aurum Technology > CCNP, CCDA, MCSE, CNE > > ""Ken Yeo"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Hi, > > > > We are having problem to browse this website: > > > > www.sitemeter.com > > > > Internet explorer will say "Opening page http://www.sitemeter.com"; in the > > status bar on the bottom and the page never came up. It came back with > > error: > > > > The page cannot be displayed > > We are able to browse the site using dialup to Netzero and some other dial > > up ISP. > > I wonder those of you who use PIX try this site? > > Our first thought was reserve DNS was not setup so we setup reserve DNS > for > > the NATed IP on the PIX, but still cannot browse the site. Any ideas? > > Thanks, > > Ken Yeo > > Network Engineer, > > Aurum Technology > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=2403&t=2403 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Cisco Question [7:2447]
If you had to select just one answer I would say DTE as there are also non-CPE routers. If you want to be really picky you could say there are routers acting as DCE also, but this usually requires some additional configuration and is not usally the default behavior. HTH. "[EMAIL PROTECTED] (Katson Yeung)" wrote: > I would say the router is a DTE and also is a CPE. > > On 29 Apr 2001 02:52:50 -0400, [EMAIL PROTECTED] ("Victim") wrote: > > >What is the wide area networking acronym that describes the default router > >device type? > > > >a. DTE > >b. DCE > >c. CPE > >d. CO > >FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=2479&t=2447 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: CCIE written test questions [7:2497]
1) In short Fast Link Pulse (FLP) is used to perform autonegotiation on twisted pair media. For details see: See: http://cisco.com/warp/public/473/46.html 2) TCP slow start is flow control mechanism employed by the sender. This allows the sender to probe the maximum window size it may use for transmisson without significantly impacting throughput. It starts by transmitting data in one window chunks of a size specified by the lowest MSS advertised by each host. The transmitter calls this window the congestion window (cwnd). For each ACK received the congestion window is increase by one. Only cwnd segments may be outstanding at any one time. This increases until packets begin to be dropped. This results in an exponential growth of the number of segments that will be transmitted before recieving an ACK. See: - TCP/IP illustrated by W. Richard Stevens - "Congestion Avoidance and Control," V. Jacobson, ACM SIGCOMM-88, August 1988. 3) The CSU/DSU should go into loopback mode and instead of passing data through its framer and on to the DTE it should send the data back to the network. This is useful for circuit testing. --trey scott mann wrote: > Hello all, > > I have three questions that I cannot seem to find the answer to. ANy of you > learned people out there would be very much appreciated if you could give me > your best shot at these. I have my written tommorow and these questions are > stuck in my craw; > > What is Fast Link Pulse? > > What is meant by TCP "Slow Start"? > > What is the result of sending a loop up signal to the CSU/DSU? > > I eagerly await any input. > > Thanks, > Scott > > _ > Get your FREE download of MSN Explorer at http://explorer.msn.com > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=2515&t=2497 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BGP Route Reflector Question. [7:2900]
next-hop-self on the route-reflector will work here. --trey - Original Message - From: "RAJESH.V.S" To: Sent: Wednesday, May 02, 2001 12:26 PM Subject: BGP Route Reflector Question. [7:2900] > Hi All, > > Got a Doubt on BGP Route Reflectors. BGP uses route reflectors to simplify > the IBGP mesh configuration. > Say a RR reflects an IBGP route announced by RRclient-1 to another RR > client say, RRClient-2. The RR keeps the next hop of the IBGP network > announced by RRclient-1 un-altered while announcing to RRclient-2. Now if > the next hop i.e. RRClient-1 is inaccessible to RRclient-2 , RRClient-2 > will not advertise that route to its peers ( EBGP/IBGP). And IBGP peers can > be many hops away ( i.e. not directly connected/in same subnet). As per BGP > doc from Cisco , even if you use next-hop-self, only EBGP next hops will be > altered, not Reflected IBGP next hops. So in a large IBGP only network ( no > other IGP ), how will you ensure the connectivity to all the links between > RRClient nexthops? > > Will they use any IGP or static route for this purpose ?. Or you have to > manipulate the point where you advertise each IBGP networks to contain > next-hop subnets also ?. Or is there any mistake in my understanding ?. > > Please advice, > > Thanks in advance > Regards > Rajesh > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=2907&t=2900 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Route descriptor blocks???? [7:3104]
Route Descriptor Blocks (and Interface Descriptor Blocks IDBs) are internal data structures that can not be configured directly. They store the necessary information about routes and interfaces in memory. --trey tim sullivan wrote: > All, > Does any have a link to a good explaination of what > a descriptor block is/does/gets config'd...I ahve searched the > CISCO site but do not get a clear pix.Not that I missed the > the doc on that tiny little site of theirs. > > Thanks > Tim > _ > Get your FREE download of MSN Explorer at http://explorer.msn.com > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=3125&t=3104 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Interpretation of some BGP commands [7:2997]
This will result in the announcement of 202.161.128.0/19 (128-160), the AGGREGATOR attribute will be set and longer prefixes in this subnet will be suppressed. --trey suaveguru wrote: > hi , > > can anyone tell me what the command below summarises > the address to be ? > > network 202.161.128.0 mask 255.255.224.0 > aggregate-address 202.161.128.0 255.255.224.0 > summary-only > > regards, > > suaveguru > > __ > Do You Yahoo!? > Yahoo! Auctions - buy the things you want at great prices > http://auctions.yahoo.com/ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=3126&t=2997 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: real world BGP question [7:3506]
Those /24s likely have something to do with the fact that the blocks in the A space you mentioned are ARIN allocated CIDR blocks. I believe that ISPs tend to be a little less restrictive on them. Several other route-servers mirror your findings on cerf.net. For those of you that haven't seen it: http://www.arin.net/regserv/IPStats.html#cidr --trey Chuck Larrieu wrote: > I respectfully disagree. A brief look through route-server.cerf.net shows an > awful lot of /24's in class A space, particularly in the 24.0.0.0, 64.0.0.0, > 65.0.0.0, and 66.0.0.0 space. Not to mention a lot in class B space. My hand > hurts from scrolling through the routing table there. Granted, everything is > relative. What cerf.net shows is not necessarily what any other provider > shows. But I suggest that CIDR is broken and there are lots of prefixes > longer than /19, no matter what the classful block. :-> > > Chuck > > -Original Message- > From: Brian [mailto:[EMAIL PROTECTED]] > Sent: Monday, May 07, 2001 5:05 PM > To: Chuck Larrieu > Cc: [EMAIL PROTECTED] > Subject:RE: real world BGP question [7:3506] > > many providers filter based on the classful origin of the space. If the > block is out of what was once class a or b space, the likelihood of a /24 > getting filtered out is fairly high. My previous employer did that. > > Brian "Sonic" Whalen > Success = Preparation + Opportunity > > On Mon, 7 May 2001, Chuck Larrieu wrote: > > > Seems rather presumptuous of Cisco to speak for every ISP in the world > > > > In order to limit the number of routes being advertised on the internet, I > > believe it was considered "best current practice" to limit prefix length > to > > /19 or shorter. ( can't find the RFC at the moment, but I recall it being > > referenced several times in various threads on the NANOG list. ) > > > > Obviously, with well over 100K routes in "the internet routing table" > there > > are a great number of longer prefixes being advertised, no doubt in great > > part because of the number of companies that are "connected to multiple > > ISP's so they can load balance across the internet" > > > > Prefix advertising my be influenced by peering arrangements, downstream > and > > upstream agreements, and customer requirements. Generally, once holes are > > punched through CIDR blocks, what can anyone do? > > > > When someone makes a statement like you attribute to Cisco, one must > always > > follow up with specifics to determine what is really meant. Not all routes > > seen in one provider's network routing tables are necessarily present in > the > > tables of another provider. > > > > Chuck > > > > > > -Original Message- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > > Murphy, Brennan > > Sent: Monday, May 07, 2001 4:01 PM > > To: '[EMAIL PROTECTED]'; Charlie Winckless; Murphy, Brennan > > Cc: [EMAIL PROTECTED] > > Subject: RE: real world BGP question > > > > Cisco told me today that a /24 drawn from Class C space > > has a better chance of being propogated throughout the Internet > > than a /24 taken from Class B space. Anyone disagree with that? > > Can anyone recommend a good source of info on this. Ive checked > > Halabi. > > > > I came across a good reference during my quest www.traceroute.org > > Unfortunately, it doesnt offer plain answers to my questions. > > > > > > -Original Message- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] > > Sent: Friday, April 27, 2001 1:58 PM > > To: Charlie Winckless; 'Murphy, Brennan' > > Cc: [EMAIL PROTECTED] > > Subject: Re: real world BGP question > > > > > > Currently on a US basis a /24 would generaly work. Internationaly > (Europe) > > most providers would filter out anywhing longer then /20. > > > > > > - Original Message - > > From: "Charlie Winckless" > > To: "'Murphy, Brennan'" > > Cc: > > Sent: Friday, April 27, 2001 1:18 PM > > Subject: RE: real world BGP question > > > > > > > I used to work for VERIO. At that time they would not > > > router smaller than /19 on their backbone. > > > > > > This may have changed. > > > > > > > -Original Message- > > > > From: Murphy, Brennan [mailto:[EMAIL PROTECTED]] > > > > Sent: Friday, April 27, 2001 10:46 AM > > > > To: 'Michelle T'; '[EMAIL PROTECTED]' > > > > Subject: RE: real world BGP question > > > > > > > > > > > > I guess that is my real question: what is the longest prefix that > > > > is exchanged among/between major carriers. > > > > > > > > The real world example here is what if you had 4 server farms > > > > answering > > > > to one DNS name: ftp.foo.com You have Round Robin DNS running > > > > round trip times to match a user with their nearest server farm > > > > so it sends back the closest/fastest IP. The question is, how > > > > big do those > > > > subnets for the server farms have to be in order to be maximally > > > > advertised throughout the internet? > > > > > > > > So, I've seen two answers