oa-systemd may not respond via DBUS, if it is executing a long running process.
- Possible Reason 1: Sometimes the oaconfig install fails if a related Ceph cluster is in state error or warning
- Possible Reason 2: rbd du is called synchronously, thus may block the oa-systemd indefinitely
- Possible Reason 3: rbd du may take up to 70 minutes (e.g. called from ceph.tasks.get_rbd_performance_data)
- Possible Reason 4: Writing the Nagios configs calls CephRbd.objects.all() for each Ceph pool. If every call to CephRbd.objects.all() hangs till a timeout ExternalCommandError, DBUS run into a timeout
- Possible Reason 5: Unstable network connection between openATTIC and the Ceph cluster