In looking through the logs, I see that lxc/1 was picked to be created first, but creating the template container failed. So, the queued up lxc/0 tries to start and sees that the template container doesn't exist. Juju then tries to create the template and does so successfully. So, it was in fact the juju-trusty-lxc-template container that failed, but was successfully created during the second attempt.
Saw a similar error message reported by someone else earlier this year where Tycho had helped out, so I pinged Tycho to see if he could take a look in this case too.
In looking through the logs, I see that lxc/1 was picked to be created first, but creating the template container failed. So, the queued up lxc/0 tries to start and sees that the template container doesn't exist. Juju then tries to create the template and does so successfully. So, it was in fact the juju-trusty- lxc-template container that failed, but was successfully created during the second attempt.
Saw a similar error message reported by someone else earlier this year where Tycho had helped out, so I pinged Tycho to see if he could take a look in this case too.