When we are using friendly names for multipath the multipaths are not
getting flushed, which may lead to data loss on slow connections and
multipath entries with no actual paths.
This happens in both iSCSI and FC connections, and it is due to the
flush being requested on the WWN instead of the actual name of the
device.
So when we are not using friendly names the WWN and the device name are
the same and our call to multipath -f will successfully flush remaining
data, but when we are using friendly names they will not match, and the
call to multipath -f will silently fail (return code 0) and the flush
will not actually go through. When the flush doesn't happen, if there is
remaining data, then the multipath will stay once the individual paths
have been removed.
Closes-Bug: #1663925
Change-Id: Ib93d945a5b5fca57bcac4e176d62d1412b95f2da
c0640ce137