With change[1], we added a mechanism to wait for multipath
device to be ready for I/O. see more info in [2].
Sometimes the connection to the storage array is slow and
the multipath device doesn't get discovered during the
os-brick operation.
This leads to failure while waiting for the multipath device
where we don't even have the multipath device populated yet
in /sys/block/<dev>/holders/dm-* resulting in the following
command executing and failing.
'multipath -C None'
This does indicate some issue with the connection but we
should not fail the operation here since we can still
complete it even with a single device discovered.
This is already handled in the iSCSI connector[3] with a check
for the sysfs dm name being populated or not.
This patch adds the same logic to FC where the dm name is
not populated but we don't want to fail the operation
because of slow connection.
Closes-Bug: #2097388
[1] https://review.opendev.org/c/openstack/os-brick/+/920516
[2] https://launchpad.net/bugs/2067949
[3] 5f5a8f7563/os_brick/initiator/connectors/iscsi.py (L788-L792)
Change-Id: Ie8860d05841cc3222871da55bdddd6b7f8135850
8ac46333d7