We caught it here:

https://openstack-ci-reports.ubuntu.com/artifacts/test_charm_pipeline_amulet_full/openstack/charm-ceph-osd/318611/1/2016-05-19_14-00-50/index.html

2016-05-19 14:52:30 DEBUG worker.uniter.jujuc server.go:173 hook context id "cinder/0-install-2328604234966462243"; dir "/var/lib/juju/agents/unit-cinder-0/charm"
2016-05-19 14:52:30 INFO install error: private-address not set
2016-05-19 14:52:30 INFO install Traceback (most recent call last):
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/install.real", line 579, in <module>
2016-05-19 14:52:30 INFO install     assess_status(CONFIGS)
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/cinder_utils.py", line 886, in assess_status
2016-05-19 14:52:30 INFO install     assess_status_func(configs)()
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 1530, in _assess_status_func
2016-05-19 14:52:30 INFO install     state, message = _determine_os_workload_status(*args, **kwargs)
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 930, in _determine_os_workload_status
2016-05-19 14:52:30 INFO install     configs, required_interfaces)
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 984, in _ows_check_generic_interfaces
2016-05-19 14:52:30 INFO install     required_interfaces)
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 1265, in incomplete_relation_data
2016-05-19 14:52:30 INFO install     complete_ctxts = configs.complete_contexts()
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 295, in complete_contexts
2016-05-19 14:52:30 INFO install     for i in six.itervalues(self.templates)]
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 120, in complete_contexts
2016-05-19 14:52:30 INFO install     self.context()
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 105, in context
2016-05-19 14:52:30 INFO install     _ctxt = context()
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/contrib/openstack/context.py", line 592, in __call__
2016-05-19 14:52:30 INFO install     addr = get_host_ip(unit_get('private-address'))
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/core/hookenv.py", line 74, in wrapper
2016-05-19 14:52:30 INFO install     res = func(*args, **kwargs)
2016-05-19 14:52:30 INFO install   File "/var/lib/juju/agents/unit-cinder-0/charm/hooks/charmhelpers/core/hookenv.py", line 624, in unit_get
2016-05-19 14:52:30 INFO install     return json.loads(subprocess.check_output(_args).decode('UTF-8'))
2016-05-19 14:52:30 INFO install   File "/usr/lib/python2.7/subprocess.py", line 573, in check_output
2016-05-19 14:52:30 INFO install     raise CalledProcessError(retcode, cmd, output=output)
2016-05-19 14:52:30 INFO install subprocess.CalledProcessError: Command '['unit-get', '--format=json', 'private-address']' returned non-zero exit status 1