IPv6: Extra Route is failing

in IPv6 use-case: extra-routes for a normal router is failing.

The FIB Entry has been created but after that it hasn't been translated into Table 21 flows.

Steps (openstack newton):

1. Create IPv6 subnet with GUA, create a router, add this subnet to router.
2. Spawn 2 neutron ports in this created IPv6 subnet with attributes:

--allowed-address ip_address=2001:db9:abcd:d::/64
--allowed-address ip_address=2001:db9:cafe:d::/64,

where:

2001:db9:abcd:d::/64
2001:db9:cafe:d::/64

are extraroutes

3. launch two VMs (VM1, VM2), attached to created neutron ports.

4. Put an extra-route with one of the VMs as the nexthop for that router using:

Openstack router-update <router-name> destination=extra-route,nexthop=VM1-ip

5. Ping the extra-route from VM2 and it will not work.