Routing Problems with Floating routes not kicking back. - Page 2

hks10 · ‎10-12-2005

Experiencing static routes not kicking back from floating routes in different PE's.

Scenario:

We have a static route in PE1 pointing to an interface for a leased line. We also have the same subnet with a admin distance of 220 route in another PE2 for a fail over. When the main static route in PE1 fails the floating route in PE2 kicks in right away but then will not go away out of the routing tables in all the PE's when the main static route comes back up. I have to manually go into PE2 and remove the floating route to remedy this. Is there another way or am I missing something to remedy this between PE's? Any help would be appreciated.

olorunloba · ‎10-13-2005

I tried to simulate it in a lab, and it did not work. You can try it also. BGP kept preferring the redistributed route because of the higher weight.

nz-ipv6 · ‎10-13-2005

guys,

I had to use AS-PATH pre pend. Local preference is fine if both the routes are being advertised within same AS.

In my setup, floating statics were from one AS and BGP routes were coming from different AS. and these were separated by a third party AS.

HKS

I will look into your config,once I get chance. I am in the middle of an IPT design. Hopefully before Saturday, I should be able to respond to you.

Have a good day

attrgautam · ‎10-13-2005

If your setup is still up, can you remove the redistribution of the Static Route with AD 220 into BGP in PE2 and see if it still prefers the Static route. I suspect that it is installing the static route after the redistribution. Sorry for the trouble. Iam planning to test this too. tHKS

Regds

hks10 · ‎10-14-2005

Hi Attrgautam thanks for the advice. Last night I've been testing all the posted ideas in this forum and what I tried was I created a route-map w/lower local preference and redistributed the route-map(static) in the vrf and that seem to remedy the problem that I was having.It now kicks back and forth w/o any problems.

address-family ipv4 vrf cust1

redistribute connected

redistribute static route-map cust1

no auto-summary

no synchronization

exit-address-family

!

route-map cust1 permit 10

set local-preference 50

hks10 · ‎10-14-2005

Hi olorunloba your absolutely right on the money with this. After all the changes the local route is still prefered on pe2. Would you know of a way I can change or set a weight for the static floating routes?

attrgautam · ‎10-14-2005

Rather you can increase the weight you are receiving from the other PE router.

ip extcommunity-list 100 match RT:100:100

route-map set-weight

match extcommunity 100:100

set weight 64000

address-family vpnv4

neighbor PE1 route-map set-weight in

This will work. But before this can you remove redistribution of the static route ( it should hav AD 220) in PE2 and check if it prefers the BGP learnt route

olorunloba · ‎10-15-2005

I think it will be neater to keep the config together. We only need to reduce the weight of the redistributed static route in BGP, so that the local pereference can be the deciding attribute. By matching on the community (applying to the VPN session) you are not sure of the other prefixes it will apply to, and therefore other effects it could have.

Surely, without the redistribution, the BGP learnt route is preferred (AD 200 against AD 220)

Modifying the config you gave then, you can try this