EIGRP Backup Route Issue(s)

[adamtodd16]

Looking for some assistance with EIGRP backup routing. Here is the scenario: 

CAMPUS setup with multiple sites tied together via layer 2 (fiber, wireless, etc.) with layer 3 routing.  Routes advertised with EIGRP 10

Some of these sites have a router as the HSRP backup device. These routers connect back to the HUB via DMVPN with routes being advertised via EIGRP 40. 

The HUB has both EIGRP 40 and 10 and is advertising the 10 routes across 40. 

When I add EIGRP 40 to the backup router, the hub drops the EIGRP 10 routes and uses the 40 routers. 

Hope the above makes sense - look forward to hearing your suggestions. 

Thanks!

[Jon Marshall]

Is the hub router for the DMPVN tunnels the same router as the one which is used for connectivity to the other sites using EIGRP 10 ?

Jon

[adamtodd16]

It's the Internet GW for the sites using EIGRP10 and receiving route updates, but not handling EIGRP/Static Routers for EIGRP 10. 

[Jon Marshall]

It's the Internet GW for the sites using EIGRP10 and receiving route updates, but not handling EIGRP/Static Routers for EIGRP 10. 

Perhaps a quick topology diagram would help showing which routers do what.

So are you saying the hub router receives EIGRP routes from the DMPVN branches via AS 40 and also routes for the same subnets from another router for EIGRP AS 10.

If so then I assume the metrics are simply better from the DMVPN tunnels and that is why it is dropping the AS 10 routes.

Why does it matter as the hub should only be used in case of a failure so not traffic should go via the hub unless a remote site loses it main connection.

Perhaps you could clarify with an example of a route and explain what the main issue is.

Jon

[Jon Marshall · Accepted solution]

Adam

Sorry, I am half watching football and I really didn't think that last answer through.

Obviously if it is the internet gateway it needs EIGRP 10 routes.

Have you thought about adding a delay to the tunnel interface on the hub so the metrics are better for EIGRP 10 routes ?

Once again, sorry, it's not even that good a match to be honest :-)

Jon

[adamtodd16]

Ha! No problem Jon, I know that feeling well! 

Thanks for helping me get my head on straight today. Simply added distance EIGRP 90 90 to force the distance the same for internal / external and metrics started working as required. 

[Jon Marshall]

Ahh, I thought all the routes were EIGRP internals but it sounds like they weren't.

Glad to hear you got it working despite my rather poor efforts to help :-)

Jon

[adamtodd16]

Sometimes that all it takes to trigger some common sense :) hope the match got more enjoyable!