On Thu, Mar 5, 2026 at 6:14 PM Sascha Lucas via ceph-users <[email protected]> wrote: > > Hi Matthias, > > On Thu, 5 Mar 2026, Matthias Riße via ceph-users wrote: > > > I ran into this issue too and was quite puzzled. There is this open PR which > > suggests that group snapshot exports are unsupported as of now: > > https://github.com/ceph/ceph/pull/40808 > > Thanks for your fast reply. I was afraid of that the group feature is not > yet much usable for: no export, no clone, no mirror. Just snap/rollback > works. The IBM version supports group mirror[1]. But I don't know if this > feature will stay an exclusive enterprise one? > > The mentioned PR is old and outdated. Seems not a prominent feature ...
Hi Sascha, To see the image-level snapshots that comprise a group snapshot taken with "rbd group snap create", run "rbd snap ls --all". There is no support for cloning from a group snapshot directly but cloning from the corresponding image-level snapshots is possible with "rbd clone <image name> --snap-id <snap id>" syntax (instead of the usual "rbd clone <image name>@<snap name>"). As a workaround one can do that for each member image and then create a new group out of the resulting clone images. The new "clone" group wouldn't get linked to the original "parent" group like clone images get linked to their parent images though. Unfortunately there is no support for exporting a group snapshot directly (you already saw the unfinished PR) and even being able to export the corresponding image-level snapshots individually is pending on https://tracker.ceph.com/issues/72410. As a workaround one can clone from an image-level snapshot and then export the clone image. > > > The best thing I could figure out to get consistent snapshots with multiple > > rbd's is to fsfreeze my filesystems (using libvirt, so domfs{freeze,thaw} in > > my case) and make individual snapshots of the rbd images. > > Yes, I already considered this "workaround", but I'm not using libvirt, so > have to talk to qemu-guest-agent my self. See my reply to Matthias -- involving qemu-guest-agent to freeze the filesystems before taking the snapshot is actually a superior option, so I wouldn't refer to it as a workaround. Thanks, Ilya _______________________________________________ ceph-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
