Store the flush_thread of a node as a class object. Before starting a
new flush thread (either flush or unflush), stop the existing one if it
exists to prevent further migrations, then start the new thread. Set the
object to None on init and again once the task actually finishes. Remove
the inflush flag as this is not required when using these threads and
functionally does nothing any longer, but add the flush_stopper flag to
trigger cancellation of the current job.
This just seemed like more trouble that it was worth. Flush locks were
originally intended as a way to counteract the weird issues around
flushing that were mostly fixed by the code refactoring, so this will
help test if those issues are truly gone. If not, will look into a
cleaner solution that doesn't result in unchangeable states.
Without this, the IPMI information set during initial node creation can
never be changed, which can cause issues later. Instead, always set it
fresh on each node boot.
Store a basic list of RBD disks in Zookeeper for access by the node
subsystem to handle RBD locks. This avoids the need to implement complex
parsing logic inside the fencing configuration (or elsewhere).
Also handle a malformed XML content properly during VM define.
Similar to recent client changes, don't replace the previous node record
of an already-migrated VM. Wait for shutdown if required. Use a
continue statement instead of a needless else block.
Previous to this, if once force-migrated a VM, the previous_node value
would be updated to the current node, which is likely never what an
administrator would want. Change this functionality so that the previous
node value is not changed, and update the documentation to reflect this.