qvo ports are not removed correctly when an instance is deleted immediately after creation

[Ashutosh Tiwari]

Release version:
Neutron: stable/Ussuri
(Open vSwitch) 2.11.1

on searching the issue i see this raised earlier on Mirantis Openstack,
https://bugs.launchpad.net/mos/+bug/1711637

As mentioned in the link above, this is leading to excessive logging at OVS,

2021-10-22T03:40:02.728Z|311606|coverage(revalidator631)|INFO|Skipping details of duplicate event coverage for hash=4a9bb48e
2021-10-22T03:43:50.650Z|123897195|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:51.017Z|123897196|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:51.843Z|123897197|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:52.208Z|123897198|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:52.487Z|123897199|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:52.856Z|123897200|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:54.179Z|123897201|bridge|WARN|could not open network device qvoda000ab6-48 (No such device)
2021-10-22T03:43:54.622Z|123897202|poll_loop|INFO|Dropped 17 log messages in last 4728 seconds (most recently, 4726 seconds ago) due to excessive rate

ovs-vsctl shows some 100+ ports with vlan tag 4095.

[Jakub Libosvar (libosvar)]

Hi Ashutosh,

is there any impact on the functionality of the given compute node? If the port is not deleted in Nova and reused for the same instance, does the instance networking work?

[Ashutosh Tiwari (ashuttiw)]

@libosvar thanks for looking into it.

There is no impact on running instances. Also there is no corresponding ports in neutron for the qvo ports listed.
The problem with this is logging from OVS. This is filling up the disk space unless ports are deleted manually from ovs.

[Slawek Kaplonski (slaweq)]

AFAIR qvo and qvb ports are created and deleted by os-vif (nova) and not by neutron. So I don't think this is an Neutron bug really and I'm moving it to os-vif for now.