Missing qvb and qvo Veth pairs on compute node

asked 2015-07-08 09:55:52 -0500

bobyakov gravatar image

Hi Guys,

Ran into an issue where compute node froze and I had to force reboot it. After it came up, Couldn't get the instance to start. I discovered on the compute node that I have the qbr Bridge and Tap interface, but the veth pairs are missing. Can I manually add them back in and how if i can?

cwtcpt042:~$ brctl show:

bridge name     bridge id               STP enabled     interfaces
qbrf547ed17-e7          8000.fe163e7314ec       no              tapf547ed17-e7
qbrfec36fc5-4c          8000.fe163e8ff337       no              tapfec36fc5-4c
virbr0          8000.000000000000       yes

cwtcpt042:~$ sudo ovs-vsctl show:

 Bridge br-int
        fail_mode: secure
        Port br-int
            Interface br-int
                type: internal
        Port patch-tun
            Interface patch-tun
                type: patch
                options: {peer=patch-int}
    ovs_version: "2.0.2"
edit retag flag offensive close merge delete

2 answers

Sort by ยป oldest newest most voted

answered 2015-07-08 10:00:21 -0500

SamYaple gravatar image

Restarting the neutron plugin agent on the compute node should recreate everything you need, unless there are other issues with OVS.

ovs_version: "2.0.2" Is a known bad version. You really shouldn't be using anything less than 2.1, preferably 2.3.1.

The kilo cloud-archive has packages for ovs 2.3.1, I suggest adding that repo and pinning the OVS packages to get that later version.

edit flag offensive delete link more


I tried restarting openvswitch-switch and neutron-plugin-openvswitch-agent, still missing qvo and qvb.. Is there another service that needs to be restarted?

Also, I'm using Ice house, should I be concerned about updating OVS only?

bobyakov gravatar imagebobyakov ( 2015-07-08 10:18:53 -0500 )edit

Updating OVS is safe and recommended. I have seen many issues with 2.0.2. I would recommend the latest OVS before pursuing these issues further to rule that out.

SamYaple gravatar imageSamYaple ( 2015-07-09 02:03:46 -0500 )edit

Should I use OpenVswitch, Ubuntu or Openstack repository?

bobyakov gravatar imagebobyakov ( 2015-07-09 08:12:33 -0500 )edit

Can you clarify something please, if I add https://launchpad.net/~ubuntu-cloud-a... repository, when I do updates on Ice house won't it install the latest services for all not just OVS? How can I limit this update to OVS only?

bobyakov gravatar imagebobyakov ( 2015-07-09 12:06:49 -0500 )edit

Had to restart services and then instance seems to have worked. I tried to add tap manually, shouldn't have.

bobyakov gravatar imagebobyakov ( 2015-07-09 13:54:26 -0500 )edit

answered 2016-12-29 16:54:20 -0500

I had a tap and a qbr port but no qvb or qbo. Restarting neutron services did not change anything. Restarting nova services on the compute node added those ports back.

edit flag offensive delete link more

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2015-07-08 09:55:52 -0500

Seen: 1,070 times

Last updated: Jul 08 '15