RIP & OSPF redistribution

[Tom Mazowski]

We are setting up a new network with about 20 locations, connected by several fiber rings, using a combination of ProCurve models. Some are 2920's that only support RIP, and we are trying to redistribute between OSPF and RIP at multiple points in the network. On the RIP side, I'm only sending in a default route, bu we are seeing some sub-optimal routing going from the core (OSPF) to the RIP sites. This is due to the fact that when we bring the RIP routes into OSPF, we lose the hop cound, and they all end up with the same metric.

I'll probably switch to RIP across the board, but figured I'd see if anyone out there has any suggestions on fine-tuning the redistribution.

Thanks for any advice.

[Mike_ES · Accepted solution]

Hello Tom,

What I can see, there is a need to use route-maps (aka "route-policy") during redistribution from RIPv2 to OSPF process.

By route-maps you could influence your OSPF metric (cost) for selected links - primary and backup for RIPv2 site.

We need to see more on your routing topology.

Cheers,

Michal 

[Tom Mazowski]

I was able to figure out a solution, & a route-map did the trick. Below is what I came up with. This is bringing the RIP routes into OSPF with the same RIP metric, and then the metric increases along each hop in the OSPF domain. Changing the external metric type to E1 ensures that the metric increases when routes are redistributed into OSPF. I also have a route map for OSPF going into RIP, since we are only sending the RIP comain a default route.

route-map "RIPtoOSPF" permit seq 10
match metric 1
match source-protocol rip
set metric 1
set metric-type external type-1
exit
route-map "RIPtoOSPF" permit seq 20
match metric 2
match source-protocol rip
set metric 2
set metric-type external type-1
exit
route-map "RIPtoOSPF" permit seq 30
match metric 3
match source-protocol rip
set metric 3
set metric-type external type-1
exit