BGP route Manipulation

[MahmoudDawoud0323]

Hello Guys,

Here is the design and the objective:-

We have R1,R2 and R3 all connected via a core switch and from R3-R1 there is iBGP and from R3 to R2 there is iBGP too, now from LAN side the traffic goes to R3 always via VRRP. R2 and R1 both have an eBGP to a backbone MPLS.

For simplicity lets say R1 and R2 only knows a total of 4 subnets learnt and they will advertise that into iBGP, now when traffic go to R3 we need to make R1 primary and R2 secondary,the challenge is:- We need to have one of those 4 subnets to be preferred from R2 instead of R1 , so when R3 wants to go to that subney , it uses backup instead of primary.

Any thoughts?

If you have can you share the config.

I tried using local pref for that specific prefix on backup router to be higher than primary router for R3 but it ended up changing all the prefixes advertised from backup to R3 being all higher :S

Can someone help ? Thanks

[MahmoudDawoud0323]

Hi Paul,

Issue solved when I replaced the prefix-list with an ACL, any explanation ?

[paul driver]

Hello
Your route-map doesn’t seem to be matching the prefix-list.

Example:
route-map xx
match ip address <acl> = access-list
or
match ip address prefix-list <prefix list> =prefix-list