I have a 3 replica cluster. A couple times I have run into inconsistent PGs. I googled it and ceph docs and various blogs say run a repair first. But a couple people on IRC and a mailing list thread from 2015 say that ceph blindly copies the primary over the secondaries and calls it good. http://lists.ceph.com/pipermail/ceph-users-ceph.com/2015-May/001370.html I sure hope that isn't the case. If so it would seem highly irresponsible to implement such a naive command called "repair". I have recently learned how to properly analyze the OSD logs and manually fix these things but not before having run repair on a dozen inconsistent PGs. Now I'm worried about what sort of corruption I may have introduced. Repairing things by hand is a simple heuristic based on comparing the size or checksum (as indicated by the logs) for each of the 3 copies and figuring out which is correct. Presumably matching two out of three should win and the odd object out should be deleted since having the exact same kind of error on two different OSDs is highly improbable. I don't understand why ceph repair wouldn't have done this all along. What is the current best practice in the use of ceph repair? Thanks! -- Tracy Reed -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 198 bytes Desc: not available URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20170217/1d713c7d/attachment.pgp>
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