effectively breaking EIGRP / BGP redistribution count-to-infinity loops

sct0321 · ‎02-05-2009

My environment is a 2 router and 2 Multihomed MPLS providers running EIGRP and BGP with redistribution. When I have failovers between MPLS providers I run into random infinity loops. Is there a way where I could establish the 2 BGP AS numbers to be shared. I think that would help the looping issues with redistribution.

Giuseppe Larosa · ‎02-05-2009

Hello Scott,

if you have multiple points of mutual redistribution you need to implement routing policies.

A useful tool are route-tags you can mark with a route-tag routes injected into EIGRP from BGP.

route-map BGP-to-eigrp deny 10

match route-tag 5000

route-map BGP-to-EIGRP permit 20

set route-tag 1000

the route-map for EIGRP to BGP will do the opposite

route-map eigrp-to-BGP deny 10

match route-tag 1000

route-map eigrp-to-BGP permit 20

set route-tag 5000

do this on both CE routers using consistent route-tag mappings

router eigrp 1000

red bgp 1000 route-map BGP-to-eigrp

default-metric 10000 1000 1 1 1500

This protects the network during transitions.

Hope to help

Giuseppe