I'm going through something similar, and it seems like the double backfill you're experiencing is about par for the course. According to the CERN presentation (http://www.slideshare.net/Inktank_Ceph/scaling-ceph-at-cern slide 19), doing a 'ceph osd crush rm osd <ID>' should save the double backfill, but I haven't experienced that in my 0.80.5 cluster. Even after I do a crush rm osd, and finally remove it via ceph rm osd.<ID>, it computes a new map and does the backfill again. As far as I can tell, there's no way around it without editing the map manually, making whatever changes you require and then pushing the new map. I personally am not experienced enough to feel comfortable making that kind of a change. Adeel > -----Original Message----- > From: ceph-users [mailto:ceph-users-bounces@xxxxxxxxxxxxxx] On Behalf Of > Dinu Vlad > Sent: Monday, December 15, 2014 11:35 AM > To: ceph-users@xxxxxxxxxxxxxx > Subject: Proper procedure for osd/host removal > > Hello, > > I've been working to upgrade the hardware on a semi-production ceph > cluster, following the instructions for OSD removal from > http://ceph.com/docs/master/rados/operations/add-or-rm- > osds/#removing-osds-manual. Basically, I've added the new hosts to the > cluster and now I'm removing the old ones from it. > > What I found curious is that after the sync triggered by the "ceph osd out > <id>" finishes and I stop the osd process and remove it from the crush map, > another session of synchronization is triggered - sometimes this one takes > longer than the first. Also, removing an empty "host" bucket from the crush > map triggred another resynchronization. > > I noticed that the overall weight of the host bucket does not change in the > crush map as a result of one OSD being "out", therefore what is happening is > kinda' normal behavior - however it remains time-consuming. Is there > something that can be done to avoid the double resync? > > I'm running 0.72.2 on top of ubuntu 12.04 on the OSD hosts. > > Thanks, > Dinu > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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