Only networks of a certain size are going to require a separate distribution and core layer. In many smaller networks these two layers are collapsed into the same devices. Your core layer should be designed to do 1 thing, switch traffic as fast as possible. Your distribution layer is where you might apply service to the traffic such as access lists, QOS, policy based routing, etc.
I think the general idea is that you need less and less ports. So your access layer switches require a lot of ports, but on less expensive switches. Your distribution layer requires less ports than the access layer, since you are just up-linking the access layer switches and not end users, however these switches usually are more $ per port. Then your core layer requires even less ports because it is only up-linking your distribution layer, but these ports may be very expensive (10GB Ethernet) and run on a higher end chassis such as a 6500. Hope that helps, Marc On Thu, Mar 3, 2011 at 10:37 PM, Narendra <[email protected]> wrote: > hi guys > > i tried too much to understanding three layer hirerichal model of > networking > but still i m confuse between distribution layer and core layer. > > please tell the difference between distribution layer and core layer with > the suitable example. > > regards > Narendra > > On Fri, Mar 4, 2011 at 4:46 AM, <[email protected]> > wrote: > > > Send CCIE_RS mailing list submissions to > > [email protected] > > > > To subscribe or unsubscribe via the World Wide Web, visit > > http://onlinestudylist.com/mailman/listinfo/ccie_rs > > or, via email, send a message with subject or body 'help' to > > [email protected] > > > > You can reach the person managing the list at > > [email protected] > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of CCIE_RS digest..." > > > > > > Today's Topics: > > > > 1. Re: fundamentals - VTY transport input / VTY ACLs / SNMP > > (Hammer) > > 2. Re: errata (Dave Blank) > > 3. Volume #1: Lab 19 (Lemish, Christopher) > > 4. Re: Volume #1: Lab 19 (Di Bias, Steve) > > 5. Re: Volume #1: Lab 19 (Lemish, Christopher) > > 6. Re: Volume #1: Lab 19 (Jay Taylor) > > 7. Re: Volume #1: Lab 19 (Trony Tigno) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Thu, 3 Mar 2011 12:36:28 -0600 > > From: Hammer <[email protected]> > > To: Rogelio Gamino <[email protected]> > > Cc: "[email protected]" <[email protected]> > > Subject: Re: [OSL | CCIE_RS] fundamentals - VTY transport input / VTY > > ACLs / SNMP > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset=ISO-8859-1 > > > > What you are saying makes sense to me. I'm just wondering if a more > > stringent CoPPs policy could be used in place of the VTY ACL. > Understanding > > that the CoPPs policy already could be used to replace control plane > > specific access on the serial/Ether/ATM type interfaces..... > > > > > > -Hammer- > > > > "I was a normal American nerd." > > -Jack Herer > > > > > > > > > > > > On Wed, Mar 2, 2011 at 6:26 PM, Rogelio Gamino <[email protected]> > wrote: > > > > > See comments below... > > > > > > > > > On Mar 2, 2011, at 4:35 PM, Hammer wrote: > > > > > > > So if you apply an ACL to the VTY that says permit ip host 10.10.10.1 > > > host > > > > 1.1.1.1 (lo0 on router) eq 22 and you have transport input telnet VTY > > > lines > > > > then the only thing you have done is forced yourself to telnet to > your > > > > router over port 22. > > > > > > I don't think the ACL changes the port the management protocol (ie. > > telnet, > > > ssh) listens on. I think you would use the rotary command under the VTY > > to > > > do that. > > > > > > > > > > > Here's my confusion. Is this redundant to CoPPs? I understand with > > policy > > > > maps on CoPPs I have a greater degree of control but in the end, it's > > > > redundant I think. > > > > > > My understanding of CoPP is that it is used to protect the device's CPU > > > from for example excessive connections that terminate on the device or > > any > > > packet that the device would have to process in CPU and not in > hardware. > > > CoPP not only allows you to rate limit the traffic but it also allows > you > > to > > > permit/deny the source of the traffic terminating on the device itself. > > This > > > way you don't have to apply an access-list to every L3 interface on the > > > device to protect it (which could be a pain to manage on routers with a > > lot > > > of interfaces). CoPP is also a more efficient way to protect the device > > > since it won't have to process (inspect) every packet going through it > > but > > > only traffic terminating on it. > > > > > > > > > HTH, > > > > > > Rogelio > > > > > > ------------------------------ > > > > Message: 2 > > Date: Thu, 3 Mar 2011 14:01:59 -0500 > > From: Dave Blank <[email protected]> > > To: Alef <[email protected]> > > Cc: [email protected] > > Subject: Re: [OSL | CCIE_RS] errata > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset=ISO-8859-1 > > > > >example 2 : Lab 1 detailed solutions page 25 > > >the frame-relay interface-dlci command does not work as expected, you > get > > the error message it is already assigned. again, not >according to the > > response given in the detailed solutions guide. I fixed this by using the > > clear frame-relay inarp command and quickly >setting up the interface > > before > > the entries were populated again. > > > > This can happen if frame-relay is configured and the interface is up > before > > "no frame-relay inverse-arp" is configured. A dynamic mapping may have > > already been created (check "show frame map"). As you mentioned a "clear > > frame inarp" will resolve this. After you disable inverse-arp you > > shouldn't > > need to do anything "quickly"... inverse arp will no longer be running. > > > > -Dave > > > > > > On Thu, Mar 3, 2011 at 10:21 AM, Alef <[email protected]> wrote: > > > > > Hi Marko, > > > It's not frame relay, i don't think i said anything about that besides > > > requesting normal help. It's the output for mismatches in the vlan > > listings > > > for example. Or the mismatches in expected behaviour as per by the > book. > > If > > > you want i can write down the errata as i come along and sent it to > you, > > but > > > it won't be my main objective. > > > > > > example 1: Lab 2 detailed solutions 2.1 > > > the sh vlan brief outputs, specifically the port assignments, don't > match > > > with what is put on the router with loading the initial configs. > > > > > > example 2 : Lab 1 detailed solutions page 25 > > > the frame-relay interface-dlci command does not work as expected, you > get > > > the error message it is already assigned. again, not according to the > > > response given in the detailed solutions guide. I fixed this by using > the > > > clear frame-relay inarp command and quickly setting up the interface > > before > > > the entries were populated again. > > > > > > example 3: Lab 1 detailed solutions page 15 > > > the VLAN listings for Cat1 and Cat2 have the names for vlan 200 and 300 > > > mixed up. For a lot of these things i thought it wast the pod not > loading > > > properly, but compare to page 10 and 11 if you wish. They are tiny > > things, > > > but as you know tiny things can be frustrating,can lead to huge > > > misunderstandings and to be honest it does take away from my lab time > > which > > > is not cheap. Am not talking semantics here either (looking an hour > into > > > things is not semantics)I could be wrong ofcourse, but i checked it > > > thoroughly and does seem to pop up quite a lot and that only for the > > first 2 > > > lab is not very stimulating as i'm sure you'd understand. Although the > > guide > > > is very comprehensive (i am using that to learn actually) and i am > happy > > > with the material, i just wanted to let you guys know about these > things > > and > > > hopefully improve them. > > > > > > ironically, yes it will help me become better at troubleshooting, but > > > unintended as per the guide :-) > > > > > > > > > > > > On 3 Mar 2011, at 14:48, Marko Milivojevic wrote: > > > > > > > > > > > Alef, > > > > > > > > From what I see, most of your issues come from FrameRelay mapping > > issues. > > > This is expected IOS behavior and not an error in our material. > > > > > > > > -- > > > > Marko Milivojevic - CCIE #18427 > > > > Senior Technical Instructor - IPexpert > > > > > > > > FREE CCIE training: http://bit.ly/vLecture > > > > > > > > Mailto: [email protected] > > > > Telephone: +1.810.326.1444 > > > > Web: http://www.ipexpert.com/ > > > > > > > > On Thu, Mar 3, 2011 at 03:36, Alef <[email protected]> wrote: > > > > Be that as it may, the amount of errors in the listings i see keeps > me > > > more busy figuring things out then actually working on the labs > > themselves. > > > It's seriously not funny anymore. With all due respect, I did not pay > 3k > > for > > > the books to instead download the softcopies you know. > > > > > > > > I am not talking about (so far) errors in commands, i am talking > about > > > the output of listings i see that don't match up. As i am wondering if > > > that's actually due to the pod not loading up properly (which is quite > > the > > > pain as well) i am constantly looking at the layer 2 connectivity > diagram > > to > > > see which one it is. > > > > > > > > Alef > > > > > > > > On 2 Mar 2011, at 15:20, Marko Milivojevic wrote: > > > > > > > >> > > > >> Hello Alef, > > > >> > > > >> From time to time, there are indeed errors in the material, but most > > of > > > it gets corrected when reported. To ensure the most up-to-date material > > with > > > corrected errors, have you downloaded the latest revision of our > > workbooks > > > from your student account on IPexpert.com? > > > >> > > > >> -- > > > >> Marko Milivojevic - CCIE #18427 > > > >> Senior Technical Instructor - IPexpert > > > >> > > > >> FREE CCIE training: http://bit.ly/vLecture > > > >> > > > >> Mailto: [email protected] > > > >> Telephone: +1.810.326.1444 > > > >> Web: http://www.ipexpert.com/ > > > >> > > > >> > > > >> On Wed, Mar 2, 2011 at 02:56, Alef <[email protected]> wrote: > > > >> I hope there's not to many mistakes like this in the workbooks, i > just > > > spend 30 minutes figuring out why things are not working, the listings > > for > > > the vlans are not consistent in the output for lab1, page 15, they mix > up > > > vlanE (200) and vlanF (300). > > > >> > > > >> well good for my troubleshooting skills if that happens very often > its > > > not going to be that good for my confidence in the materials > > > >> > > > >> Regards, > > > >> Alef > > > >> _______________________________________________ > > > >> For more information regarding industry leading CCIE Lab training, > > > please visit www.ipexpert.com > > > >> > > > > > > > > > > > > > > _______________________________________________ > > > For more information regarding industry leading CCIE Lab training, > please > > > visit www.ipexpert.com > > > > > > > > > ------------------------------ > > > > Message: 3 > > Date: Thu, 3 Mar 2011 16:10:53 -0500 > > From: "Lemish, Christopher" <[email protected]> > > To: <[email protected]> > > Subject: [OSL | CCIE_RS] Volume #1: Lab 19 > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset="iso-8859-1" > > > > ? > > Guys, > > > > I'm working on the "ip sla monitor" portion of the lab and I don't have > the > > "monitor" keyword on my routers. Could someone advise? > > > > I'm running my own rack (2811's): > > > > Version 12.4(13r)T6 > > flash:c2800nm-adventerprisek9-mz.124-22.T5.bin > > > > > > R2(config)# > > R2(config)#ip sla monitor 1 > > ^ > > % Invalid input detected at '^' marker. > > > > > > > > Thank you, > > Chris > > > > This email and any files transmitted with it are confidential and are > > intended for the sole use of the individual(s) to whom they are properly > > addressed. Any use, dissemination or forwarding of this email and any > > files transmitted with it by anyone other than the intended recipient(s) > > is strictly prohibited. If you have received this email in error, please > > notify the sender by replying to this email. Black Box Corporation and > > its affiliates reserve the right to scan and monitor all e-mail traffic. > > > > > > > > ------------------------------ > > > > Message: 4 > > Date: Thu, 3 Mar 2011 16:52:48 -0500 > > From: "Di Bias, Steve" <[email protected]> > > To: "Lemish, Christopher" <[email protected]>, > > "[email protected]" <[email protected]> > > Subject: Re: [OSL | CCIE_RS] Volume #1: Lab 19 > > Message-ID: > > < > > 2fe030039b8ad14eb4373ca25779c63e9192481...@corp-exvs01.corp.uhsinc.biz> > > > > Content-Type: text/plain; charset="us-ascii" > > > > I think the syntax is different in this IOS version. > > > > Instead of "ip sla monitor 1" it's probably "ip sla 1" > > > > Try "ip sla ?" > > > > You may want to up your IOS version by the way > > > > HTH > > > > > > > > > > -----Original Message----- > > From: [email protected] [mailto: > > [email protected]] On Behalf Of Lemish, Christopher > > Sent: Thursday, March 03, 2011 1:11 PM > > To: [email protected] > > Subject: [OSL | CCIE_RS] Volume #1: Lab 19 > > > > ? > > Guys, > > > > I'm working on the "ip sla monitor" portion of the lab and I don't have > the > > "monitor" keyword on my routers. Could someone advise? > > > > I'm running my own rack (2811's): > > > > Version 12.4(13r)T6 > > flash:c2800nm-adventerprisek9-mz.124-22.T5.bin > > > > > > R2(config)# > > R2(config)#ip sla monitor 1 > > ^ > > % Invalid input detected at '^' marker. > > > > > > > > Thank you, > > Chris > > > > This email and any files transmitted with it are confidential and are > > intended for the sole use of the individual(s) to whom they are properly > > addressed. Any use, dissemination or forwarding of this email and any > > files transmitted with it by anyone other than the intended recipient(s) > > is strictly prohibited. If you have received this email in error, please > > notify the sender by replying to this email. Black Box Corporation and > > its affiliates reserve the right to scan and monitor all e-mail traffic. > > > > _______________________________________________ > > For more information regarding industry leading CCIE Lab training, please > > visit www.ipexpert.com > > > > > > UHS Confidentiality Notice: This e-mail message, including any > > attachments, is for the sole use of the intended recipient (s) and may > > contain confidential and privileged information. Any unauthorized > review, > > use, disclosure or distribution of this information is prohibited. If > this > > was sent to you in error, please notify the sender by reply e-mail and > > destroy all copies of the original message. > > > > ------------------------------ > > > > Message: 5 > > Date: Thu, 3 Mar 2011 16:57:12 -0500 > > From: "Lemish, Christopher" <[email protected]> > > To: "Di Bias, Steve" <[email protected]>, > > <[email protected]> > > Subject: Re: [OSL | CCIE_RS] Volume #1: Lab 19 > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset="iso-8859-1" > > > > ? > > Thanks Steve! > > > > I actually took notes on the video and looked back at it. Joe configured > > it as "ip sla 1" and the threshold and schedule cmds were there. I'm > good. > > > > Thanks a lot bud! > > > > Chris > > > > > > ________________________________ > > > > From: Di Bias, Steve [mailto:[email protected]] > > Sent: Thu 3/3/2011 4:52 PM > > To: Lemish, Christopher; [email protected] > > Subject: RE: Volume #1: Lab 19 > > > > > > > > I think the syntax is different in this IOS version. > > > > Instead of "ip sla monitor 1" it's probably "ip sla 1" > > > > Try "ip sla ?" > > > > You may want to up your IOS version by the way > > > > HTH > > > > > > > > > > -----Original Message----- > > From: [email protected] [mailto: > > [email protected]] On Behalf Of Lemish, Christopher > > Sent: Thursday, March 03, 2011 1:11 PM > > To: [email protected] > > Subject: [OSL | CCIE_RS] Volume #1: Lab 19 > > > > ? > > Guys, > > > > I'm working on the "ip sla monitor" portion of the lab and I don't have > the > > "monitor" keyword on my routers. Could someone advise? > > > > I'm running my own rack (2811's): > > > > Version 12.4(13r)T6 > > flash:c2800nm-adventerprisek9-mz.124-22.T5.bin > > > > > > R2(config)# > > R2(config)#ip sla monitor 1 > > ^ > > % Invalid input detected at '^' marker. > > > > > > > > Thank you, > > Chris > > > > This email and any files transmitted with it are confidential and are > > intended for the sole use of the individual(s) to whom they are properly > > addressed. Any use, dissemination or forwarding of this email and any > > files transmitted with it by anyone other than the intended recipient(s) > > is strictly prohibited. If you have received this email in error, please > > notify the sender by replying to this email. Black Box Corporation and > > its affiliates reserve the right to scan and monitor all e-mail traffic. > > > > _______________________________________________ > > For more information regarding industry leading CCIE Lab training, please > > visit www.ipexpert.com > > > > > > UHS Confidentiality Notice: This e-mail message, including any > > attachments, is for the sole use of the intended recipient (s) and may > > contain confidential and privileged information. Any unauthorized > review, > > use, disclosure or distribution of this information is prohibited. If > this > > was sent to you in error, please notify the sender by reply e-mail and > > destroy all copies of the original message. > > > > > > > > This email and any files transmitted with it are confidential and are > > intended for the sole use of the individual(s) to whom they are properly > > addressed. Any use, dissemination or forwarding of this email and any > > files transmitted with it by anyone other than the intended recipient(s) > > is strictly prohibited. If you have received this email in error, please > > notify the sender by replying to this email. Black Box Corporation and > > its affiliates reserve the right to scan and monitor all e-mail traffic. > > > > > > > > ------------------------------ > > > > Message: 6 > > Date: Thu, 3 Mar 2011 17:17:24 -0500 > > From: Jay Taylor <[email protected]> > > To: "Lemish, Christopher" <[email protected]> > > Cc: [email protected] > > Subject: Re: [OSL | CCIE_RS] Volume #1: Lab 19 > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset=ISO-8859-1 > > > > I don't know of a 'monitor' option to the 'ip sla' command. Configuring > it > > should start with 'ip sla #' and that will take you into sla > configuration > > mode. > > > > > > On Thu, Mar 3, 2011 at 4:10 PM, Lemish, Christopher < > > [email protected]> wrote: > > > > > ? > > > Guys, > > > > > > I'm working on the "ip sla monitor" portion of the lab and I don't have > > the > > > "monitor" keyword on my routers. Could someone advise? > > > > > > I'm running my own rack (2811's): > > > > > > Version 12.4(13r)T6 > > > flash:c2800nm-adventerprisek9-mz.124-22.T5.bin > > > > > > > > > R2(config)# > > > R2(config)#ip sla monitor 1 > > > ^ > > > % Invalid input detected at '^' marker. > > > > > > > > > > > > Thank you, > > > Chris > > > > > > This email and any files transmitted with it are confidential and are > > > intended for the sole use of the individual(s) to whom they are > properly > > > addressed. Any use, dissemination or forwarding of this email and any > > > files transmitted with it by anyone other than the intended > recipient(s) > > > is strictly prohibited. If you have received this email in error, > please > > > notify the sender by replying to this email. Black Box Corporation and > > > its affiliates reserve the right to scan and monitor all e-mail > traffic. > > > > > > _______________________________________________ > > > For more information regarding industry leading CCIE Lab training, > please > > > visit www.ipexpert.com > > > > > > > > > ------------------------------ > > > > Message: 7 > > Date: Thu, 3 Mar 2011 15:16:02 -0800 > > From: Trony Tigno <[email protected]> > > To: Jay Taylor <[email protected]> > > Cc: [email protected] > > Subject: Re: [OSL | CCIE_RS] Volume #1: Lab 19 > > Message-ID: > > <[email protected]> > > Content-Type: text/plain; charset=ISO-8859-1 > > > > This is from a lab router: > > > > R2(config)#ip sla ? > > monitor IP Service Level Agreement Monitor > > > > R2(config)#ip sla mon > > R2(config)#ip sla monitor ? > > <1-2147483647> Entry Number > > group Group configuration or Group scheduling > > key-chain Use MD5 authentication for IP SLA Monitor > control > > message > > logging Enable logging > > low-memory Configure low water memory mark > > reaction-configuration IP SLA Monitor Reaction Configuration > > reaction-trigger IP SLA Monitor trigger assignment > > reset IP SLA Monitor Reset > > responder Enable IP SLA Monitor Responder > > restart Restart an active entry > > schedule IP SLA Monitor Entry Scheduling > > > > R2(config)#ip sla monitor > > % Incomplete command. > > > > R2(config)#do sh ow ver > > sh ow ver > > ^ > > % Invalid input detected at '^' marker. > > > > R2(config)#do show ver > > Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9-M), Version > > 12.4(25), RELEASE SOFTWARE (fc2) > > > > > > On Thu, Mar 3, 2011 at 2:17 PM, Jay Taylor <[email protected]> wrote: > > > > > I don't know of a 'monitor' option to the 'ip sla' command. Configuring > > it > > > should start with 'ip sla #' and that will take you into sla > > configuration > > > mode. > > > > > > > > > On Thu, Mar 3, 2011 at 4:10 PM, Lemish, Christopher < > > > [email protected]> wrote: > > > > > > > ? > > > > Guys, > > > > > > > > I'm working on the "ip sla monitor" portion of the lab and I don't > have > > > the > > > > "monitor" keyword on my routers. Could someone advise? > > > > > > > > I'm running my own rack (2811's): > > > > > > > > Version 12.4(13r)T6 > > > > flash:c2800nm-adventerprisek9-mz.124-22.T5.bin > > > > > > > > > > > > R2(config)# > > > > R2(config)#ip sla monitor 1 > > > > ^ > > > > % Invalid input detected at '^' marker. > > > > > > > > > > > > > > > > Thank you, > > > > Chris > > > > > > > > This email and any files transmitted with it are confidential and are > > > > intended for the sole use of the individual(s) to whom they are > > properly > > > > addressed. Any use, dissemination or forwarding of this email and > any > > > > files transmitted with it by anyone other than the intended > > recipient(s) > > > > is strictly prohibited. If you have received this email in error, > > please > > > > notify the sender by replying to this email. Black Box Corporation > and > > > > its affiliates reserve the right to scan and monitor all e-mail > > traffic. > > > > > > > > _______________________________________________ > > > > For more information regarding industry leading CCIE Lab training, > > please > > > > visit www.ipexpert.com > > > > > > > _______________________________________________ > > > For more information regarding industry leading CCIE Lab training, > please > > > visit www.ipexpert.com > > > > > > > > > End of CCIE_RS Digest, Vol 62, Issue 10 > > *************************************** > > > > > > -- > Best Regards, > > Narendra Prasad > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
