Seems to be no support for tap interfaces - Unexpected vif_type=tap

[jcat]

nova-lxd fails to launch an instance on a compute host when the network type uses tap interfaces in stead of bridged interfaces.

We use Calico for networking, and it seems that this doesn't work for Mitaka on Xenial at least.

It fails with this error:

2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] Traceback (most recent call last):
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/nova_lxd/nova/virt/lxd/operations.py", line 555, in cleanup
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] self.unplug_vifs(instance, network_info)
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/nova_lxd/nova/virt/lxd/operations.py", line 335, in unplug_vifs
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] instance=instance)
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] self.force_reraise()
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] six.reraise(self.type_, self.value, self.tb)
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/nova_lxd/nova/virt/lxd/operations.py", line 328, in unplug_vifs
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] self.vif_driver.unplug(instance, viface)
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] File "/usr/lib/python2.7/dist-packages/nova_lxd/nova/virt/lxd/vif.py", line 191, in unplug
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] _("Unexpected vif_type=%s") % vif_type)
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf] NovaException: Unexpected vif_type=tap
2017-03-13 14:57:38.365 28215 ERROR nova_lxd.nova.virt.lxd.operations [instance: beeae088-ae26-4c75-9169-1c77f98513bf]

System info:

Description: Ubuntu 16.04.2 LTS
Release: 16.04

nova-compute-lxd:
  Installed: 13.2.0-0ubuntu1.16.04.1
  Candidate: 13.2.0-0ubuntu1.16.04.1
  Version table:
 *** 13.2.0-0ubuntu1.16.04.1 500
        500 http://ubuntu-srv.ocado.com/xenial_r2 xenial-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     13.0.0-0ubuntu3 500
        500 http://ubuntu-srv.ocado.com/xenial_r2 xenial/main amd64 Packages

Please let me know if you need any further info.

Thanks.

[Stéphane Graber (stgraber)]

Nothing to do with LXD, targeting to nova-lxd.

[James Page (james-page)]

As the nova-lxd driver is largely untested with anything other than ML2/OVS, I'd not be surprised if this does not work in the context of Calico.

[James Page (james-page)]

That said we did get a contribution via tigera to support Calico:

   https://github.com/openstack/nova-lxd/commit/4a9c7356c01ebba1cbad9d84af709cfece3ca850

but that was not introduced until 14.0.0 (Newton).

[James Page (james-page)]

Would it be possible for you to try to reproduce this with OpenStack >= Newton, rather than Mitaka which we know does not have this support.

[jcat (jcat)]

Sorry James - this was fixed in 14.0.0 by the a patch from the calico guys.
I backpacked the patch to the 13.2 mitaka packages, and it works.

I should have come back and closed the issue - it just slipped my mind.

[jcat (jcat)]

For info: http://git.openstack.org/cgit/openstack/nova-lxd/commit/?id=c9b2950723e45850ba915f8b96389818177d41c7

[James Page (james-page)]

I'd be happy to consider including this fix into the stable/mitaka branch; we're still maintaining that atm as it was the first GA release so quite a few people are using it still.

[jcat (jcat)]

For what it's worth, here's the debian patch I've applied.