I have a situation where I need to have our GRE tunnel being decaped on our edge router however the physical terminating interface for the subnet sent over the GRE tunnel is on a different router.
I have this working well on a single router, but for other reasons I now need to split it across two routers.
Edge is where the GRE tunnel is configured.
the aaa.aaa.aaa.0/24 network is sent to us from our ISP via the GRE tunnel
The aaa network is configured on the physical i/f on core.
Assume for now that the link between edge and core is 10.0.0.1<---->10.0.0.2
I have the following
int tunnel 0
ip unnumbered FastEthernet0
ip mtu 1472
tunnel source FastEthernet0
tunnel destination xxx.xxx.xxx.xxx
On the core
int fastethernet 1
ip address aaa.aaa.aaa.1 255.255.255.0
I need to do a couple of things (where I need help).
1. Tell the traffic exiting the tunnel to route to the core router.
2. Tell traffic coming in from other i/f with a source add of aaa.aaa.aaa.0/24 to go via the tunnel.
1. Tell the traffic ingress from FE1 to route over to the core router.
I tried playing around with some static routes and an route-map but could not get it working properly (ended up with some routing loops, etc).