dual stack / configuring secondary extra route ipv6 address / not reachable

scenario

create a router, 2 subnets ipv4/ipv6 within the same network.

attach those subnets to the router

start a VM.

on the router, create 2 extra routes ipv4 and ipv6 toward that VM

https://logs.opendaylight.org/sandbox/vex-yul-odl-jenkins-2/netvirt-csit-1node-openstack-ocata-gate-stateful-oxygen/1/log_03_vpn_basic_dualstack_one_router.html.gz

observation

"test Add Multiple Extra Routes And Check Datapath Before L3VPN Creation fails" because IPv6 extra route is not reachable.