BGP not to include loopback ip addresses

Unanswered Question
Dec 1st, 2009
User Badges:

I have a 7206 router configured with ingress sub-interfaces.  I need only one of the two networks, including loopback that associated with it, to be included in BGP routing process.  In other words, I want to exclude one loopback ip address ( loopback 0) and one /27 LAN from BGP routing on router.

Current BGP router configured process:


router bgp 65xxx
no synchronization
bgp router-id 14x.x.x.240
bgp log-neighbor-changes
network 14x.x.x.240 mask 255.255.255.255
neighbor GCP peer-group
neighbor GCP remote-as 65321
neighbor 14x.x.x.245 peer-group GCP
neighbor 14x.x.x.245 description ** BGP chvpkre1 **
neighbor 14x.x.x.245 ebgp-multihop 255
neighbor 14x.x.x.245 update-source Loopback1


need to block/filter out from BGP routing process:

Loopback 0

ip address 13x.x.x.240 255.255.255.255

14x.x.138.0 255.255.255.224


allow into BGP routing process:

Loopback 1

ip address 14x.x.x.240 255.255.255.255

14x.x.137.0 255.255.255.224



any suggestions?


thanks, Kevin

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Laurent Aubert Tue, 12/01/2009 - 20:14
User Badges:
  • Cisco Employee,

Hi Kevin,


I don't understand this configuration:



Loopback 1

ip address 14x.x.x.240 255.255.255.255

14x.x.137.0 255.255.255.224


Do you mean secondary address ?


Also you are using loopback 1 as your source address for your eBGP peering. In this case, this loopback should not be announced into BGP as it could create a recursive loop during the lookup (BGP next-hop learned inside BGP -> very bad)


HTH


Laurent.

Actions

This Discussion

Related Content