Hi Sergey,
  Thanks much for the explanation!  That is reassuring and is very sensible.
  A wishlist suggestion would be to call this situation something other than 
"degraded".  Maybe merely "backfilling"?  Well, I am unfamiliar with all the 
possible states that already exist and might be appropriate.

Thanks again,
Chad.

On Friday, March 28, 2014 04:49:02 you wrote:
> On 28.03.14, 0:38, Chad Seys wrote:
> > Hi all,
> > 
> >    Beginning with a cluster with only "active+clean" PGS, adding an OSD
> >    causes
> > 
> > objects to be "degraded".
> > 
> >    Does this mean that ceph deletes replicas before copying them to the
> >    new
> > 
> > OSD?
> 
> No. Ceph adds the new OSD to the acting set of PGs going to be
> rebalanced, and number of replicas increase by 1. Replica n+1 is
> obviously missing on the new OSD so PG enters 'degraded' state.
> Once backfilling process has completed, one of OSDs that previously
> served particluar PG is removed from acting set and PG returns to
> active+clean state.
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Reply via email to