Comment 2 for bug 1765714

Hi Frode,

it happens always, in case of faulty maas credential configuration in the bundle.
Let me paste here a snippet:

# Copyright (c) 2017 Canonical USA Inc. All rights reserved.
#
# Foundation Converged
#
series: xenial
variables:
...

  # MAAS info
  maas_url: &maas_url http://100.99.5.100/MAAS
  maas_credentials: &maas_credentials e2Nr84yjuTBAYkJAqN:kZvmpm8Qt3TS9Hcv2d:jQ5waMrLWRtJWkeXpGLuqUFmyYXP3bch
  maas_source: &maas_source ""
...

machines:
  "0":
    constraints: tags=4-management
    series: xenial
  "1":
    constraints: tags=5-management
    series: xenial
  "2":
    constraints: tags=6-management
    series: xenial
...
applications:
  hacluster-cinder:
    charm: ../charms/hacluster
    options:
      cluster_count: 3
      maas_url: *maas_url
      maas_credentials: *maas_credentials
      maas_source: *maas_source
...
  cinder:
    charm: ../charms/cinder
    num_units: 3
    constraints: *ceph-access-constr
    bindings:
      "": *oam-space
      public: *public-space
      admin: *admin-space
      internal: *internal-space
      shared-db: *internal-space
    options:
      worker-multiplier: *worker-multiplier
...
    to:
    - lxd:0
    - lxd:1
    - lxd:2
...
relations:
  - [ cinder, hacluster-cinder ]
...

This is just a cut&paste, but I hope it gives you the basic idea how I have this setup.
From hereon, when I try
    juju config hacluster-cinder maas_credentials=ABCD
nothing happens in the charm, it does not handle the maas creds reconfiguration.