Juniper Contrail – how to check Next-Hop

One might need to check which MPLSoGRE/UDP/VXLAN tunnel is used to reach a specific prefix on a vrouter.

There are few steps needed to find it out after logging in to a compute node running a VM/contrainer with an interface of interest (its prefix or prefix reachable via it) :

1. List all interfaces and see which vrouter VRF a specific interface maps to:

vif --list

2. Use the VRF id to dump routes in a routing table for this VRF and check a prefix in question and its next-hop id:

rt --dump <VRF_ID>

3. Check next-hop id parameters with:

nh --get <NH_ID>