Symptom

When NHRP mappings time out, traffic coming in the VRF from MPLS gets send out via the global routing table. This seems to prevent NHRP mapping to rebuild as we would expect.

Conditions

DMVPN Tunnel is up/up but the NHRP mapping has expired due to inactivity. NAT is configured on the DMVPN Tunnel.

Workaround

Initiating traffic from the DMVPN spoke to the remote Spoke rebuilds the NHRP mapping. Removing NAT off the tunnel interface.

Further Problem Description