Thanks Ilya, Yeah maybe it should be made more explicit in the doc, but from the user point of view it's odd to have this limitation.
Regarding the kubernetes-csi-addons that enable to do VolumeReplication , promote, demote, etc directly from Kubernetes it seems very nice and I did not know this project. https://github.com/csi-addons/kubernetes-csi-addons However, we are required to avoid "beta" feature from production environment that is why journal based mirroring is not used for our kubernetes volumes. This kubernetes-csi-addons seems to be very young project : version 0.12.0 and only 21 stars in github. I am not confident to use that in production. Are you aware of production deployments using it ? Regards Le jeu. 19 juin 2025 à 00:10, Ilya Dryomov <idryo...@gmail.com> a écrit : > On Wed, Jun 18, 2025 at 7:29 PM Julien Laurenceau > <julien.laurenc...@pepitedata.com> wrote: > > > > Hi, > > > > I have 2 running ceph squid clusters (19.2.2). > > On each cluster there is an rbd pool named k8s-1 that I want to mirror > > using the snapshot based mode. > > > > if I configure both clusters in two way mirroring using the mode=image > > everything works fine. > > ``` > > rbd mirror pool enable ${mypool} image > > rbd mirror image enable ${mypool}/${myimage} snapshot > > ``` > > When I take a snapshot of myimage it gets mirrored. > > > > if I configure both clusters in two way mirroring using the mode=pool > > nothings happen. > > The snapshot are never mirrored in the second cluster. > > > > Reading the documentation > https://docs.ceph.com/en/squid/rbd/rbd-mirroring/, > > I think that the problem is that the default mode for this command is > > "journal": > > > > rbd mirror image enable {pool-name}/{image-name} {mode} > > > > But, when enabling mirror on the pool there is no way to define > > mode=journal/snapshot: > > > > rbd mirror pool enable [--site-name {local-site-name}] {pool-name} {mode} > > > > with mode=pool (default) or image. > > > > Then I think when I do : > > rbd mirror pool enable ${mypool} image > > > > I think it implicitly do : > > rbd mirror pool enable ${mypool} image journal # THIS COMMAND DOES NOT > > WORK. > > > > But I would need to have: > > rbd mirror pool enable ${mypool} image snapshot # THIS COMMAND DOES NOT > > WORK. > > > > > > In addition, when I am configured on mirror mode = pool, if I try to > > disable mirroring on an image I get the following error : > > rbd mirror image disable ${mypool}/${myimage} > > 2025-06-18T15:37:42.177+0000 7f24ec53ce00 -1 librbd::api::Mirror: > > image_disable: cannot disable mirroring in the current pool mirroring > mode > > > > Also error when I am configured on mirror mode = pool, if I try to enable > > snapshot mirroring on an image : > > rbd mirror image enable ${mypool}/${myimage} snapshot > > 2025-06-18T15:39:44.507+0000 7f533df1fe00 -1 librbd::api::Mirror: > > image_enable: cannot enable mirroring: pool is not in image mirror mode > > > > Could someone please confirm, that this is not supported ? > > Hi Julien, > > Yes, snapshot-based mirroring is possible only in "image" mode. The > "pool" mode is limited to journal-based mirroring. It's stated in the > documentation, but perhaps not explicitly enough: > > You can also mirror all images within a given pool or namespace when > using journal-based mirroring. > > > > > What is the best workaround ? Cron cephadm shell script to enable mirror > on > > all images ? > > > > PS : I do not want to use the journal based mode since the ceph-csi > mounter > > nbd is not prod-ready. > > If you are using Ceph CSI, it would be much better to drive mirroring > through Ceph CSI -- see VolumeReplication and related resources. > > Thanks, > > Ilya > _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
