neutron - qr- and qg- interfaces looses their vlan tag

[Ian Kumlien]

On a running instance, we have had several occasions of network issues.

During the last issue we noticed that the interfaces lost their vlan tags in openvswitch:
ovs-vsctl show |grep qg-fb5a3595-48 -A 10
        Port "qg-fb5a3595-48"
            Interface "qg-fb5a3595-48"
                type: internal
---

A complete restart of neutron-l3-agent caused a migration and now it works with a different vlan tag:
ovs-vsctl show |grep -A 10 qg-fb5a3595-48
        Port "qg-fb5a3595-48"
            tag: 52
            Interface "qg-fb5a3595-48"
                type: internal
---

How is this possible?

[Li Zhouzhou (lizhouzhou)]

It's possible that your port is Binding_failed.

[Ian Kumlien (pomac)]

Nothing you see in openstack, you can only see the errors in the logs and you'd notice that the machines was unreachable. Notice, this happens to running machines, machines that might have been running for months.

Anyway, this bug is so old now that it might have been fixed accidentally already.