DMVPN - Tunnel source

[BernardAK]

The question relates to using a non-physical interface for DMVPN over a primary MPLS-1, and a secondary MPLS-2 WAN environment.

Is it possible to use a loopback address as a tunnel source in DMVPN at both the Hub and the Spoke?

What would be the impact of such a configuration?

[Georg Pauwen]

Hello,

Loopback interfaces as tunnel sources should be fine, as long as there is layer 3 connectivity between the loopbacks. You would need an IGP such as EIGRP between the hub and the spoke to advertise the loopbacks.

[BernardAK]

Hello Georg,

Sorry for the late reply, as I was on sick leave. The customer has tested the use of a loopback interface in DMVPN, using BGP between the spoke and hub routers and has been satisfied with the results. Thank you for your help.

Bernard.

[Julio E. Moisa]

Hi,

Yes as Georg mentioned you can use the loopbacks, the first rule to use tunnels is to have communication between the IP addresses you are using for source and destination otherwise you can see the tunnel interface up  down. The communication between loopbacks could be enabled with any IGP or static route.

Is it a private circuit?