Comment 14 for bug 1455482

Well, that change was made for a good reason; multipath now no longer depends on scsi_id to be able to pick drives to use to multipath, and we can explicitly whitelist (or use blacklist_exclusions) devices or re-enable ID_SERIAL by modifying multipath.conf. Is this affecting other drives than the QEMU ones for your use-case?

There's still another issue though; in the installer we don't ship path selectors other than round-robin, so even if ID_SERIAL is whitelisted, you still need to modify multipath.conf to pick the round-robin selector instead of service-time -- which is now the default. I'll work on shipping service-time instead of round-robin, but the other option is to change multipath's default.