Comment 5 for bug 1978088

I am affected by this also (running Stein ovs-agent with native at large scale).

When restarting the agents, they are receiving the RPC messages that finally call add_fdb_flow function.

BUT, the first RPC loop (iter 0) may finish before all add_fdb_flow are successfully executed.

The flows that are problematic are the "flood" flows (table 22), which are not sent using "call" but "cast" on neutron RPC side [1]

[1] https://github.com/openstack/neutron/blob/5a748b7c29cb846d0de3c5e8ea3868873348c0d1/neutron/plugins/ml2/drivers/l2pop/rpc.py#L48