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Posts tagged Troubleshooting
Troubleshooting Lab #1
Mar 5th
This will be the first in a series of troubleshooting labs. I will post a topology and the issue I’m seeing. Hopefully you guys will attempt to solve it and post your ideas, questions and solutions in the comments.
We’ll start with a relatively easy one. Today we are having an issue with BGP neighbor relationships not forming.
Here’s R1′s config:
hostname R1 ! ip cef ! interface Loopback0 ip address 1.1.1.1 255.255.255.255 ! interface Serial0/0 description To R2 ip address 10.1.1.2 255.255.255.254 ! router bgp 5000 no synchronization bgp log-neighbor-changes neighbor 2.2.2.2 remote-as 6000 neighbor 2.2.2.2 ebgp-multihop 2 neighbor 2.2.2.2 update-source Loopback0 no auto-summary ! ip route 0.0.0.0 0.0.0.0 10.1.1.3 |
And R2:
hostname R2 ! ip cef ! interface Loopback0 ip address 2.2.2.2 255.255.255.255 ! interface Serial0/0 description To R1 ip address 10.1.1.3 255.255.255.254 ! router bgp 6000 no synchronization bgp log-neighbor-changes neighbor 1.1.1.1 remote-as 5000 neighbor 1.1.1.1 ebgp-multihop 2 neighbor 1.1.1.1 update-source Loopback0 no auto-summary ! ip route 0.0.0.0 0.0.0.0 10.1.1.2 |
Now some show commands:
R2#sh ip bgp summ BGP router identifier 2.2.2.2, local AS number 6000 BGP table version is 1, main routing table version 1 Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 1.1.1.1 4 5000 0 0 0 0 0 never Active R1#sh ip bgp summ BGP router identifier 1.1.1.1, local AS number 5000 BGP table version is 1, main routing table version 1 Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 2.2.2.2 4 6000 0 0 0 0 0 never Active |
We see that the relationship will not form. You guys tell me why.
I’m attaching the .net file, with it and the configs above you should be able to replicate this easily.
The Troubleshooting Lab #1 .net file
(Don’t forget to change your paths)
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