[pve-devel] [PATCH v3 qemu-server 08/11] blockdev: convert drive_mirror to blockdev_mirror

[DERUMIER, Alexandre]

>>the path referenced in the running VM is stable. the path you are
>>looking for in the graph is not. e.g., the path might be something
>>some storage software returns. or udev. or .. and that can change
>>with any software upgrade or not be 100% deterministic in the first
>>place.
>>
>>let's say you start the VM today and the path returned by the RBD
>>storage plugin is /dev/rbd/XYZ, so that is how the blockdev is
>>opened/the path is recorded. in two weeks, ceph gets updated and now
>>the udev rule or the storage plugin code changes to return the more
>>deterministic /dev/rbd/POOL/XYZ. now the paths don't match anymore.
>>(this is just an example where such a thing happened in practice
>>already ;)).

Yes, got it, thanks!


I have  begin to work on the v4 with all your comments, I think it
should work with hash of volid, now that I have fixed the live
renaming. (that was really the main blocker)

I'll try to send a v4 before the fosdem 

Thanks for the review and your time !