Hi Ben, thank you for the quick answer!
> btrfs includes its own logical volume management and can spread a > filesystem across multiple devices, so in general it has to use UUIDs > to find the devices for a filesytem. Still it shouldn't change the block device name for a mounted filesystem. > I agree that this interacts poorly with block-level snapshot > mechanisms. If you want to have multiple versions of a btrfs > filesystem, I think you have to use btrfs snapshots. Yeah, but that is incompatible with DRBD replication (which works on the level below).