1. The destination state on an error was invalid; should be "stop".
2. If a lock was listed but removing it fails (because it was already
cleared somehow, this would error. In turn this would cause the VM to
not migrate and be left in an undefined state. Fix that when unlocking
is forced.
1. Move fence monitoring to its own thread rather than doing the listing
and triggering within the main keepalive thread.
2. Add a global lock key at /config/fence_lock and use this lock key to
prevent multiple nodes from trying to run fences simultaneously.
3. Run the fencing monitor for each node sequentially within the context
of the main fence monitoring thread, to ensure that fences of multiple
nodes happen sequentially rather than in parallel.
All of these should help to prevent any anomalies where one node can try
to fence multiple nodes at once without recourse.
This is still needed due to the nature of the locks and freeing them on
startup, and to preserve lock=fail behaviour on VM startup.
Also fixes the fencing lock flush to directly use the client library
outside of Celery. I don't like this hack but it seems prudent until we
move fencing to the workers as well.
Use a power off (and then make the power on a requirement) during a node
fence. Removes some potential ambiguity in the power state, since we
will know for certain if it is off.
1. Output from ipmitool was not being stripped, and stray newlines were
throwing off the comparisons. Fixes this.
2. Several stages were lacking meaningful messages. Adds these in so the
output is more clear about what is going on.
3. Reduce the sleep time after a fence to just 1x the
keepalive_interval, rather than 2x, because this seemed like excessively
long even for slow IPMI interfaces, especially since we're checking the
power state now anyways.
4. Set the node daemon state to an explicit 'fenced' state after a
successful fence to indicate to users that the node was indeed fenced
successfully and not still 'dead'.
This branch commit refactors the pvcnoded component to better adhere to
good programming practices. The previous Daemon.py was a massive file
which contained almost 2000 lines of direct, root-level code which was
directly imported. Not only was this poor practice, but this resulted
in a nigh-unmaintainable file which was hard even for me to understand.
This refactoring splits a large section of the code from Daemon.py into
separate small modules and functions in the `util/` directory. This will
hopefully make most of the functionality easy to find and modify without
having to dig through a single large file.
Further the existing subcomponents have been moved to the `objects/`
directory which clearly separates them.
Finally, the Daemon.py code has mostly been moved into a function,
`entrypoint()`, which is then called from the `pvcnoded.py` stub.
An additional item is that most format strings have been replaced by
f-strings to make use of the Python 3.6 features in Daemon.py and the
utility files.