EIGRP over GRE Tunnel

[Michael Durham]

I have an office router with networks 192.168.100.x and 192.168.200.x.  I also have a remote home office router what also has the 192.168.100.x and 192.168.200.x networks.  These two routers are connected over the internet via an encrypted tunnel.  The home office only has one PC and one Cisco IP phone..  All is working now but every time I want access a new device at the office from home, I need to enter a static route to it.  The office router is a Cisco 3925 and the home router is a Cisco 1921 and both are using IOS 15.7.

I tried enabling EIGRP on both sides but it does not seem to work.

My goal is to be able to ping and connect to a printer at work to my home PC without having to add a specific static router to the printer.
The home PC's IP is 192.168.100.21  I tried putting this on both routers:

router eigrp 9001
network 192.168.100.0
network 192.168.200.0
neighbor 192.168.100.1 Tunnel200

Any suggestions?  Thank You

[Francesco Molino]

Hi

Quick question : is eigrp mandatory?
I'm saying that because you only have 2 subnets on each site so you would be able to do nat to avoid overlapping and use static routes.
This would be an easy fix and easy implementation.
Or have you already thought about that and have a specific use case which wouldn't work in that design?

[e.ciollaro]

Hi,

if you are using an IPSec tunnel, EIGRP can't work properly because EIGRP use multicast that is not supported over IPSec. If you really need EIGRP, configure GRE over IPSec to support mutlicast or try to configure EIGRP to work with unicast:

routye eigrp <as>
neighbor <ip> <interf>

In any case I suspect that EIGRP does not resolve your problem because home office router has, in its routing table, networks 192.168.100.x and 192.168.200.x as connected and therefore with a best admin metric then EIGRP. So it would always try to reach host with address 192.169.100.x and 192168.200.x locally and not over the tunnel.  As suggested by Francesco, the best thing to to is using NAT

Bye

enrico