memcache:93
error: invalid value "memcache:93" for flag -r: relation not found
Traceback (most recent call last):
  File "./hooks/memcache-relation-joined", line 19, in <module>
    main()
  File "/usr/local/lib/python3.5/dist-packages/charms/reactive/__init__.py", line 73, in main
    bus.dispatch()
  File "/usr/local/lib/python3.5/dist-packages/charms/reactive/bus.py", line 421, in dispatch
    _invoke(other_handlers)
  File "/usr/local/lib/python3.5/dist-packages/charms/reactive/bus.py", line 404, in _invoke
    handler.invoke()
  File "/usr/local/lib/python3.5/dist-packages/charms/reactive/bus.py", line 280, in invoke
    self._action(*args)
  File "/var/lib/juju/agents/unit-sentry-mem-0/charm/reactive/sentry.py", line 135, in set_memcache_cfg
    for host in memcache.memcache_hosts():
  File "/var/lib/juju/agents/unit-sentry-mem-0/charm/hooks/relations/memcache/requires.py", line 37, in memcache_hosts
    return self.get_remote_all('private-address')
  File "/var/lib/juju/agents/unit-sentry-mem-0/charm/hooks/relations/memcache/requires.py", line 26, in get_remote_all
    for unit in hookenv.related_units(relation_id):
  File "/usr/local/lib/python3.5/dist-packages/charmhelpers/core/hookenv.py", line 74, in wrapper
    res = func(*args, **kwargs)
  File "/usr/local/lib/python3.5/dist-packages/charmhelpers/core/hookenv.py", line 435, in related_units
    subprocess.check_output(units_cmd_line).decode('UTF-8')) or []
  File "/usr/lib/python3.5/subprocess.py", line 626, in check_output
    **kwargs).stdout
  File "/usr/lib/python3.5/subprocess.py", line 708, in run
    output=stdout, stderr=stderr)