Comment 1 for bug 1757292

FWIW, calling setup_networks_on_host() from post_live_migration_at_destination() was added way back in Essex:

https://github.com/openstack/nova/commit/0c7a54b3b44f849bf397bb4068ab16c576c3559c

So it was primarily a nova-network thing (was Quantum even being used in Essex?).