Got Cisco 7200 Series Peering with Mikrotik over GRE tunnel.
all looks correct... peering and MD5 authetication takes place..
router are in each others neighbors able.

tunnel is up and running and can pass traffic perfectly.

Although no routes are being passed . In the Mikrotik I can see in the Network table the 2 networks defined (The loopback and the tunnel interface ) show as INVALID?

if I do the exact same thing with an ethernet cable everything works fine..
its just when running it through the tunnel..

anyone have any Ideas on this?

Thanx

Have you checked the MTU?