Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a Cisco 1801 on a remote site with dual WAN connections, with route maps to correctly NAT depending on which interface the traffic leaves via. I use IP SLA to adjust the default route from the primary interface (Dialer1) to the backup interface (Dialer0) when the primary interface goes down.

The problem I have is that I can't ping the backup interface when the primary is up, because the default route correctly directs all traffic back out of Dialer1. This is bad as it means I can't monitor the backup for failures, which means I could lose the primary only to find that the backup is also down.

I assume I need to do PBR to send traffic back out of the interface that it came from, but I can't work out how.

Do I need to do PBR on Dialer0? If so not sure what to set in order to get traffic going back out the same way. Am sure this is simple but can't seem to find the right resource to read.

share|improve this question
N.B. I found this resource… which describes using PBR to set next hops etc - but as I see it I need to set the return route? – btongeorge Jul 26 '13 at 11:47

I think you're looking for a 'local' policy route map - which would influence traffic originating from the router, as opposed to Traditional PBR which you apply to an interface and influences traffic through the router.

Im mobile so I cant effectively find the documentation right now - Im sure someone can edit this if this is the solution you're after

share|improve this answer
Yes you're right, although I want to influence traffic differently depending on which interface it came in on. In other words, I want to be able to ping both interfaces from the outside, and get responses. – btongeorge Jul 26 '13 at 13:18
Can you match intf dialer 0 and then set intf dialer 0 in a local policy route map? – Jason Seemann Jul 26 '13 at 13:54

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.