PBR Questions

[nathan.deane]

Hi,

I am working on a network design that could possibly use alot of Policy based routing and wanted to check a couple of points. the network will soley be made up of 6500's and with SUP720-VS's.

1)Can multiple policy maps be applied to different interfaces to forward the same traffic i.e. based on port numbers to two different destinations. I am assuming yes, as my understanding is that PBR can be applied globally or on interface / VLAN level.

2) If the above is correct then I also assume that traffic that is coming back into a port which it was forwarded to by PBR can be policy based routed again to a different destination.

I am fairly certain all of the above is correct but wanted to sound it out.

Thanks

[Richard Burts]

Nathan

I believe that most of what you say represents a correct understanding of PBR. There is not really a global application of PBR. The closest thing to that is the configuration of PBR for locally generated traffic (traffic generated by the router itself). Otherwise PBR is assigned at the interface level.

I have not done it myself but I know of no reason why you could not have multiple policy maps and assign different policy maps/route maps to different interfaces. Each route map could specify a different treatment for the same traffic (port number, etc) and what happens to a packet would depend on which interface it entered the router on and which policy route map was associated with that interface.

And certainly you could use PBR to route traffic going in one direction and then you could have PBR active on the interface on which response traffic was received and could make different decisions about how to route the response traffic.

HTH

Rick

[bvsnarayana03]

The return traffic can be diverted to another interface by using PBR, if the port remains the same.

If u r using PBR to match traffic based on ports, remember it'll not work with traffic on randomly changing ports.