Routing Issue with backup

cyber.noc · ‎02-13-2007

I have configured DSL PPPoE with WAN IP 11.1.1.5/32 and routed a subnet

12.1.1.0/24 (on my BRAS router). Same Pool has been routed towards ISDN as

backup (on my DIST router). The problem occurs when PPPoE goes down, routing

entry dose not take backup ISDN path. The reason behind is that my BRAS gets

next hop WAN pool 11.1.1.0/24 from Core router i.e. towards Null0 for BGP advertisment

Kindly suggest me the changes to overcome this problem. Also see attached

Diagram for better understanding.

mheusinger · ‎02-13-2007

Hi,

you should be able to solve the problem with a floating static for 11.1.1.5/32 on your BRAS pointing to your DIST router. Finally all you want is to get the packets down to your DIST router, which will then route it through the backup to the 12 network.

Did not test it, but seems worth a try. Longest match routing should then prefer /32 over the 11.1.1.0/24 announced in BGP.

Hope this helps! Please use the rating system.

Regards, Martin