... or maybe it isn't that strange, and it's just a feature. Until recently, we using a single 200GB SAN volume with our heartbeat cluster. The SAN ist a (yuck) Datacor SANsymphony Windows-based crap, but so be it. Everything was working fine. Multipath just rocked. The volume is seen twice, and dm-0 was nicely created. Later, a second 50GB volume was added from the same SAN controller - everything worked OK. After that, 3 TB sized volumes were added from a Nexsan controller. These were handled fine but the first 2 Datacor volumes were gone, i.e. no dm-X was created! Identical behaviour on both machines in the cluster. No changes whatsoever in any config file compared to the original setup (single volume). Analysis revealed that the /dev/sdX block devices were still present (sdb - sde, respectively) but all 4 devices had the same UUID! As soon as I removed one of the volumes, the remaining volume worked just fine. We even assigned the second volume to a different controller port, thus forcing a different WWN for the volume, but the UUID (scsi_id -gus <device>) remained the same. What can be wrong here? I assume dm-multipath refuses to work with what looks like the same device (by UUID) but 2 different sizes. But why is the same UUID calculated (how?) for 2 apparently different volumes? Strangely, another HB cluster with 3 Datacor SAN volumes has no such problems. Appreciate any help :-) TIA! -- Fortune's Law of the Week (this week, from Kentucky): No female shall appear in a bathing suit at any airport in this State unless she is escorted by two officers or unless she is armed with a club. The provisions of this statute shall not apply to females weighing less than 90 pounds nor exceeding 200 pounds, nor shall it apply to female horses. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
