MPLS and DMVPN

abbas.ali · ‎12-14-2009

I have a Hub and remote locations connected via MPLS as a primary path and backed up by DMVPN. During the testing, I shutdown an MPLS interface on my Remote router to make sure that remote is reachable to Hub via DMVPN router, and it was. The problem is that when I bring back the MPLS link, the routes should dynamically convereged to MPLS path, but it wouldn't. The only way to bring the routes back to MPLS is to manually shutdown/un shutdwon the Tunnel Interface on DMVPN router.

Thanks,

paolo bevilacqua · ‎12-14-2009

You cannot ask generic questions like that and expect a sensed reply.

Most likely you have a configuration error, and to find it, one would need to look at your configurations in depth and possibly even run a debug session.

Note in most cases these are paid activities by network engineers.

Giuseppe Larosa · ‎12-14-2009

Hello Alì,

Paolo is right to get better help you need to provide much more details:

what routing protocol is used on the primary MPLS links?

what routing protocol is used on the DMVPN?

if they are different, how routing information is exchanged between them = where and how have you configured redistribution?

This kind of situations: fallback ok, but restore not correct can happen when BGP is involved and redistribution is used.

But this is just generally speaking.

Hope to help

Giuseppe

abbas.ali · ‎12-14-2009

Hi giuseppe,

Your assumptions are totally correct. The MPLS is running BGP with the Provider and EIGRP that connects to Internal Core Router. Internal Core Router also connects to Separate DMVPN Router under the same EIGRP Process. DMVPN connects to Internet via BGP as well.

Yes, redistribution is done on both MPLS and DMVPN Router.

Note: The DMVPN is running two instances of EIGRP. One for the Internal Network and the other one for the Tunnel Interface with mutual redistribution. We had to do that since all the site have different EIGRP AS and the only way to setup the DMVPN is to create a separate AS for the Tunnels and then redistribute mutually for each location.

Thanks