Comment 1 for bug 1801303

can you provide more information on what neutron network backend you are using.

nova has had a feature where we wait for vif-plugged event from neutron on boot before
starting the guest. that feature was implemneted in icehouse as part of this bluepint
https://blueprints.launchpad.net/nova/+spec/admin-event-callback-api

some ml2 backends such as odl send the vif-plugged event on port bind instead of when they have completed
wireing up the port. .i.e odl send the vif-plugged event before it installs the required openflow rules.

i belive later versions of odl and networking odl actully send the vif-plugged after the openflow rules are installed but for queens
i do not think this is the case.

if you are use ml2/ovs or ml2/linux-bridge you should see this behavior.
i this is likely not a nova bug but rather a case of the ml2 driver sending the vif-plugged event before it has acutlly
finished wiring up the port intoducing a race.

if you are using ml2/ovs and can provide nova-compute and nutron agent logs for the event we can reasses.
for now i will mark this as incomplete and recommend that we close as in valid if futher info cannot be provided
as there is insuffent info currently to fully triage.