Warning! Disk unusable as pool member - serial number is not legitimate or unique.
Disk names may change unfavourably upon reboot leading to inadvertent drive reallocation and potential data loss. This error is caused by the source of these disks such as your Hypervisor or SAN. Please ensure that disks are provided with unique serial numbers before proceeding further.
I do understand the concern about “Disk names may change unfavourably upon reboot(…).”, because it happens in LInux, but this is not the case with XEN (PV). You actually tell on the hypervisor side what name it should get in the VM and it stays that way:
From the vm.cfg on the hypervisor: disk = ['file:/OVS/Repositories/0004fb00000300006530d635cb3eb558/VirtualDisks/0004fb0000120000937930df5c202a35.img,xvdb,w']
This will become /dev/xvdb in the VM, because you told it to be /dev/xvdb. If you move the disk to an other ‘slot’ manually, yes, the ‘unique-path’ changes, but I think that would be acceptable.
Also personally I think the ‘uniqueness’ of the UUID on volume level would be sufficient, because when a disk is completely empty (like an empty bucket), it starts to matter which disk it is when you put something in/on it.
I’m willing to take the risk of ‘unfavourably disk name changes’ for XEN, is there any work around for this? I have created ‘unique’ symlinks in /dev/disk/by-id: “xvdb -> …/…/xvdb” and also I see a some ‘fake-serial-’ being created.
When using Oracle VM, the default names can be transformed to UUID’s.
Don’t trust the value from the node name (51872) it’s as unique as the device name (xvdk), persistent between reboots, unless you move it to a different ‘slot’.