Comment 1 for bug 1635664

I'm seeing instances of this error in our automated testing of Landscape autopilot openstack deployments. The most recent example was with juju 1:2.1~rc1, but I also have runs with 1:2.1~beta4. Also, I first found lp:1604915, which is duped to this bug. I've seen this error four times between beta4 and rc1.

The error message seen in one of the juju unit logs is:
[from build 5173 landscape-0-inner-logs/ceilometer-1/var/log/juju/unit-ceilometer-1.log]
2017-02-02 05:12:48 ERROR juju.worker.dependency engine.go:547 "leadership-tracker" manifold worker returned unexpected error: leadership failure: lease manager stopped
2017-02-02 05:12:48 ERROR juju.worker.uniter agent.go:28 resolver loop error: could not acquire lock: cancelled acquiring mutex

The juju-status message for that unit is also set to "resolver loop error". In each instance of hitting this, it appears to be a different application. The error causes the entire deployment to fail.

Builds associated with this failure:
 - https://ci.lscape.net/job/landscape-system-tests/5263
 - https://ci.lscape.net/job/landscape-system-tests/5173
 - https://ci.lscape.net/job/landscape-system-tests/5139
 - https://ci.lscape.net/job/landscape-system-tests/5132