> Op 8 februari 2017 om 15:23 schreef Sage Weil <sage@xxxxxxxxxxxx>: > > > On Wed, 8 Feb 2017, John Spray wrote: > > So I've just finished upgrading my home cluster OSDs to bluestore by > > killing them one by one and then letting backfill happen to "new" OSDs > > on the same drives. Hooray! > > > > One slightly awkward thing I ran into was that even though I had noout > > set throughout, during the period between removing the old OSD and > > adding the "new" one, some PGs would of course get remapped (and start > > generating backfill IO to third party OSDs). This does make sense > > when you think about it (noout doesn't make the cluster magically > > remember OSDs that have been removed), but is still an undesirable > > behaviour. > > > > A) Do we currently have a mechanism to tell the cluster "even though I > > removed this OSD, don't go moving PGs around just yet"? Should we add > > one? > > There's 'ceph osd set norebalance'... > > > B) Was there a way for me to avoid this by e.g. skipping the "osd rm > > X" and "osd crush rm osd.X" that I'm currently doing before adding the > > new OSD that will take the old OSD's ID? > > This keeps coming up but I don't think we've ever proposed a good > solution. Perhaps the simplest thing is to allow ceph-disk to take an OSD > id as an argument. Normally this is probably a no-no since the OSD might > exist elsewhere and have real data on it, and you don't want multiple OSDs > with the same id, but we could make this safer by requiring that the > OSD be marked 'lost' before it's id can be reused... > Or the OSD should not exist yet? Allowing ceph-disk to re-use a ID and UUID would make it a lot easier when switching from FileStore to BlueStore as well. ceph-disk --zap-disk -i 0 --uuid XXX-XXXX-XXXX-XXXX prepare /dev/sda That way you can wipe a existing disk to BlueStore. Wido > sage > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
