Hi, On 08/10/2015 22:25, Gregory Farnum wrote: > So that means there's no automated way to guarantee the right copy of > an object when scrubbing. If you have 3+ copies I'd recommend checking > each of them and picking the one that's duplicated... It's curious because I have already tried with cephfs to "corrupt" a file in the OSD backend. I had a little text file in cephfs mapped to the object "$inode.$num" and this object was in the PG $pg_id, in the primary OSD $primary and in the secondary OSD $secondary (I had indeed size == 2). I thought that the primary OSD was always taken as reference by the "ceph pg repair" command, so I have tried this: # Test A echo "foo blabla..." >/var/lib/ceph/osd/ceph-$primary/current/$pg_id_head/$inode.$num ceph pg repair $pg_id and the "repair" command worked correctly and my file was repaired correctly. I have tried to change the file in the secondary OSD too with: # Test B echo "foo blabla..." >/var/lib/ceph/osd/ceph-$secondary/current/$pg_id_head/$inode.$num ceph pg repair $pg_id and it was the same, the file was repaired correctly too. In these 2 cases, the good OSD was taken as reference (the secondary for the test A and the primary for the test B). So, in this case, how did ceph know which copy was the correct object? -- François Lafont _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com