Setting router-id as IPv6 address when starting BGP stack leads to undefined behavior

After applying patch from https://git.opendaylight.org/gerrit/#/c/50280/ "Fix exceptions when using IPv6 vxlan tunnels", ODL can handle BGP router-id made of IPv6 address.
The issue is not the patch itself, but the fact that the BGP stack (Quagga BGP) can't support router-id larger than 32 bits.

We reproduced the issue in our lab using an ODL stub that's send thrift messages to BGP stack:

send thrift startBgp(bgp-connaddr="1::1", as="100")

=> results in bgp router-id 0.0.0.0 within quagga bgpd daemon configuration (/opt/quagga/etc/bgpd.conf), which is not good.

Is that IPv6 router-id a real need ? Note that this field is just an id, it doesn't have to be a valid ip address.

I don't think the Quagga BGP project would update it's behavior to satisfy this patch.

regards