** Description changed: [Impact] Requesting to backport to Mitaka since we are seeing this issue in Mitaka clouds (and fix landed in Newton) whereby some compute nodes fail to have their flows added to br-tun following restart of openvswitch- switch. [Test Case] * Deploy Openstack Mitaka with one compute host * Create an instance with overlay network (gre) * Make a note of flows added to br-tun (ovs-vsctl dump-flows br-tun) * systemctl restart openvswitch-switch * Check that flows are re-added to br-tun (compare with previous output) * Ensure you do not see "Interface monitor is not active" in /var/log/neutron/neutron-openvswitch-agent NOTE: the root cause of this issue is that ovsdb monitor async process that neutron-openvswitch-agent starts takes too long to start and is not active by the time the rpc_loop tries to poll for updates. It is hard to simulate this scenario and as such it is difficult to know whether it has happened and resolved by this patch. Nevertheless this patch is small and known to have resolved the issue for newer versions of Openstack. [Regression Potential] + I can't think how this patch could cause a regression. The only possible + difference could be that the rpc_loop might take longer to update flows + on ovs restart but that in itself would indicate a wider system issue + beyond the neutron service that would not constitute a regression. --------------- I noticed this error message in neutron-ovs-agent log when start neutron-openvswitch-agent ERROR neutron.agent.linux.ovsdb_monitor [req-a7c7a398-a13b-490e- adf8-c5afb24b4b9c None None] Interface monitor is not active. ovs-agent will start ovsdb_monitor at [1], and first use it at [2]. There is no guarantee that ovsdb_monitor is ready at [2]. So, I can see the error when start neutron-openvswitch-agent. We should block the start to wait for the process to be active, and then use it. Or else, the use of ovsdb_monitor will be meaningless. [1] https://github.com/openstack/neutron/blob/6da27a78f42db00c91a747861eafde7edc6f1fa7/neutron/agent/linux/polling.py#L35 [2] https://github.com/openstack/neutron/blob/6da27a78f42db00c91a747861eafde7edc6f1fa7/neutron/plugins/ml2/drivers/openvswitch/agent/ovs_neutron_agent.py#L1994
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1584647 Title: [SRU] "Interface monitor is not active" can be observed at ovs-agent start To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-archive/+bug/1584647/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
