Overcloud Update loops on IN PROGRESS and fails after 4 hours

Issue

• When following the minor update section of the fast forward upgrade doc the update command gets stuck and ultimately fails at the timeout:

$ openstack overcloud update stack -i overcloud
starting package update on stack overcloud
IN_PROGRESS
IN_PROGRESS
WAITING
on_breakpoint: [u'overcloud-compute-1', u'overcloud-cephstorage-0', u'overcloud-compute-0', u'overcloud-controller-1', u'overcloud-compute-2', u'overcloud-cephstorage-1', u'overcloud-cephstorage-2', u'overcloud-controller-2', u'overcloud-controller-0']
Breakpoint reached, continue? Regexp or Enter=proceed (will clear b08e0938-418f-45ba-b0b3-95207cf625fc), C-c=quit interactive mode:
IN_PROGRESS
IN_PROGRESS
IN_PROGRESS
IN_PROGRESS
...truncated...
IN_PROGRESS
IN_PROGRESS
FAILED
update finished with status FAILED
Stack update failed.