Juju cannot bring up agents in containers

[Curtis Hovey]

Since the merge to support lxd 2.3, all container lxd tests fail. No bundle can bring up an agent placed in container, --to 1/lxd/0. The maas container networking tests are also broken. All the failures are ambiguous timeouts, but the consistency of the failures with the new lxd changes imply something is very wrong. The logs can be found from at these examples:

http://reports.vapour.ws/releases/4452/job/aws-deployer-bundle/attempt/2144
http://reports.vapour.ws/releases/4452/job/aws-native-deploy-bundle/attempt/506
http://reports.vapour.ws/releases/4452/job/functional-container-networking-maas-1-9/attempt/94
http://reports.vapour.ws/releases/4452/job/functional-container-networking-maas-2-0/attempt/1142
http://reports.vapour.ws/releases/4452/job/functional-container-networking-maas-2-1/attempt/27
http://reports.vapour.ws/releases/4452/job/gce-deployer-bundle/attempt/2431
http://reports.vapour.ws/releases/4452/job/maas-2-0-bundle-deploy/attempt/560
http://reports.vapour.ws/releases/4452/job/maas-2-1-bundle-deploy/attempt/28
http://reports.vapour.ws/releases/4452/job/rackspace-bundle-lxd/attempt/573
http://reports.vapour.ws/releases/4452/job/rackspace-deploy-bundle/attempt/703

[Alexis Bruemmer (alexis-bruemmer)]

  https://github.com/juju/juju/pull/6386