RIP v1 and v2 Migration to EIGRP

dennis.griffiths · ‎06-04-2007

Hello Folks,

Fairly simple question (not for me, however). We have a headend router connected via FR in a hub-n-spoke fashion. There are approx. 15 remote routers also connected into the FR net. The default routing protocol is RIP v1, although all interfaces are sending and receiving RIP v1 and v2 (not sure why just yet, as there are no other commands showing any specific tuning to get v2 attributes working for efficiency). Just as a point of note, all of the remote sites are running RIP v1 by default, but some are using a "redistribute connected" in their config. Again, not sure why just yet, but need to investigate separately.

Here's my question...finally....

I was asked to help migrate the entire WAN from RIP (v1/v2) to a 100% EIGRP network. Is there a preferred plan of attack, such as migrating slowly with route redistribution mechanisms or simple enabling EIGRP as a routing protocol across all participating routers and then disabling RIP altogether?

Please advise!!! ))

ariela · ‎06-04-2007

Hi,

it depends on the number of your routes, and, first of all, the length of your maintenance window :)

You could create a parallel EIGRP infrastructure, the hub first, then spoke-by-spoke ... You'll have two routing protocols, but EIGRP will prefer for the AD, so no problems ... Last step, when all RIB will use the EIGRP ('show ip route rip' clear), delete the RIP configuration portion ...

HTH

Andrea

ankbhasi · ‎06-04-2007

Hi Dennis,

If I have to do this job then I may plan to play with admin distance. If you just start configuring EIGRP into your network, then as you start adding it to more and more routers you will get EIGRP routes displacing RIP routes due to administrative distance. You will see all your traffic going between the EIGRP routers whenever possible, even if there were better routes available through a router speaking only RIP.

I believe you can configure eigrp with admin distance say 130 which is more than admin distance for rip then once eigrp is configured on all routers then disable distance command after visiting all routers. Then once distance command is removed verify all routes are eigrp learned routes and once you are convinced all are eigrp then you can remove RIP all together.

Also while reviewing eigrp routes check for any links that aren't being used. You may have missed an interface which may not be speaking EIGRP on one or more links.

Agaian it's just one way and there can be many more. Do arrange for some downtime before proceeding the same as convergance on big network may take sometime and also if possible do take the backup of all router config before proceeding for migration.

HTH

Ankur

*Pls rate all helpfull post

Amit Singh · ‎06-04-2007

Dennis,

I would not suggest to use the route redistribution mechanism as it can result in routing loop and blck holes.

The typically used tehcnique is using the higher admin distance for the new routing protocol or a lower admin value for the currrenr routing protocol being used. Here are the example pof two scenario

1. Configuring EIGRP with a high admin distance

router eigrp 100

distance 150

This will make the admin distacne of all the EIGRP routes to 150 and when you have all the routers configured fully for EIGRP you can slowly start removing the RIP config.

2. Configure the RIP admin distance lower than the EIGRP

Router RIP

distance 50

this will make RIP routes preferred over EIGRP and you can try configruing EIGRP across all your routers. Once the config is done you can increase the admin distacne of thr RIP routes or remove the RIP process from all the routers.

The only thing that you have to take care of is the memory capacity of the routers while you will be running two routing processes. If you have few of the small capacity routers, you can see a performance impact on the routers.

HTH,Please rate if it does.

-amit singh