Il 10/10/2012 10:33, Chen HanXiao ha scritto: >> You need to use scsi-block instead of scsi-generic. However, I don't see >> how this can work. After the snapshot, the image will be qcow2, not raw, and >> thus it will not support bdrv_aio_ioctl. Hence any SCSI command (for >> scsi-generic) or any non-data SCSI command (for scsi-block) will fail. > > That's the issue what I also encountered. > Do you mean that it is impossible for us to enable snapshot for > scsi-generic?
It's impossible, and rightly so: the user could anyway bypass the snapshotting and write to the disk (WRITE SAME for example). Not just snapshot=on, which fails because it is early enough that the disk fails to initialize. Live snapshots also ought to be blocked, it is a bug that they are not. Paolo
