GRE tunnel issues

[hector.grajales1]

Hello All

It is the first time I work with GRE tunnel and I'm facing issues, because the traffic that it is supposed to going through the tunnel it is not doing.

the GRE tunnel is up, I created a route map with next-hop verify-availability and I see that the next hop is up actually I can ping it. I created an access list to associate it with the route map, But I do not see any traffic  matching the acl.

I'm working with a cisco ISR 4431 whit hte folowing IOS: System image file is "bootflash:/isr4400-universalk9.03.16.04b.S.155-3.S4b-ext.SPA.bi"

Any idea of what can be the issue?

Best regards

[Julio E. Moisa]

Hi Hector,

Could you please share the topology and the configuration applied on both devices?, if you want to move traffic through a GRE Tunnel, you must enable routing between the endpoints, using static routing or dynamic routing protocols like RIP, EIGRP, OSPF. If the GRE Tunnel is the backup, you can play with the administrative distances. 

Also please share the show ip interface brief output to see the tunnel up on both sides.  

:-)