Are you runnig with the default failure domain of 'host'? If so, with a pool size of 3 and your 20 OSDs physically only on 2 hosts Ceph is unable to find a 3rd host to map the 3rd replica.
Either add a host and move some OSDs there or reduce pool size to 2. -K. On 03/23/2016 02:17 PM, Zhang Qiang wrote: > And here's the osd tree if it matters. > > ID WEIGHT TYPE NAME UP/DOWN REWEIGHT PRIMARY-AFFINITY > -1 22.39984 root default > -2 21.39984 host 10 > 0 1.06999 osd.0 up 1.00000 1.00000 > 1 1.06999 osd.1 up 1.00000 1.00000 > 2 1.06999 osd.2 up 1.00000 1.00000 > 3 1.06999 osd.3 up 1.00000 1.00000 > 4 1.06999 osd.4 up 1.00000 1.00000 > 5 1.06999 osd.5 up 1.00000 1.00000 > 6 1.06999 osd.6 up 1.00000 1.00000 > 7 1.06999 osd.7 up 1.00000 1.00000 > 8 1.06999 osd.8 up 1.00000 1.00000 > 9 1.06999 osd.9 up 1.00000 1.00000 > 10 1.06999 osd.10 up 1.00000 1.00000 > 11 1.06999 osd.11 up 1.00000 1.00000 > 12 1.06999 osd.12 up 1.00000 1.00000 > 13 1.06999 osd.13 up 1.00000 1.00000 > 14 1.06999 osd.14 up 1.00000 1.00000 > 15 1.06999 osd.15 up 1.00000 1.00000 > 16 1.06999 osd.16 up 1.00000 1.00000 > 17 1.06999 osd.17 up 1.00000 1.00000 > 18 1.06999 osd.18 up 1.00000 1.00000 > 19 1.06999 osd.19 up 1.00000 1.00000 > -3 1.00000 host 148_96 > 0 1.00000 osd.0 up 1.00000 1.00000 > > On Wed, 23 Mar 2016 at 19:10 Zhang Qiang <dotslash...@gmail.com > <mailto:dotslash...@gmail.com>> wrote: > > Oliver, Goncalo, > > Sorry to disturb again, but recreating the pool with a smaller > pg_num didn't seem to work, now all 666 pgs are degraded + undersized. > > New status: > cluster d2a69513-ad8e-4b25-8f10-69c4041d624d > health HEALTH_WARN > 666 pgs degraded > 82 pgs stuck unclean > 666 pgs undersized > monmap e5: 5 mons at > > {1=10.3.138.37:6789/0,2=10.3.138.39:6789/0,3=10.3.138.40:6789/0,4=10.3.138.59:6789/0,GGZ-YG-S0311-PLATFORM-138=10.3.138.36:6789/0 > > <http://10.3.138.37:6789/0,2=10.3.138.39:6789/0,3=10.3.138.40:6789/0,4=10.3.138.59:6789/0,GGZ-YG-S0311-PLATFORM-138=10.3.138.36:6789/0>} > election epoch 28, quorum 0,1,2,3,4 > GGZ-YG-S0311-PLATFORM-138,1,2,3,4 > osdmap e705: 20 osds: 20 up, 20 in > pgmap v1961: 666 pgs, 1 pools, 0 bytes data, 0 objects > 13223 MB used, 20861 GB / 21991 GB avail > 666 active+undersized+degraded > > Only one pool and its size is 3. So I think according to the > algorithm, (20 * 100) / 3 = 666 pgs is reasonable. > > I updated health detail and also attached a pg query result on > gist(https://gist.github.com/dotSlashLu/22623b4cefa06a46e0d4). > > On Wed, 23 Mar 2016 at 09:01 Dotslash Lu <dotslash...@gmail.com > <mailto:dotslash...@gmail.com>> wrote: > > Hello Gonçalo, > > Thanks for your reminding. I was just setting up the cluster for > test, so don't worry, I can just remove the pool. And I learnt > that since the replication number and pool number are related to > pg_num, I'll consider them carefully before deploying any data. > > On Mar 23, 2016, at 6:58 AM, Goncalo Borges > <goncalo.bor...@sydney.edu.au > <mailto:goncalo.bor...@sydney.edu.au>> wrote: > >> Hi Zhang... >> >> If I can add some more info, the change of PGs is a heavy >> operation, and as far as i know, you should NEVER decrease >> PGs. From the notes in pgcalc (http://ceph.com/pgcalc/): >> >> "It's also important to know that the PG count can be >> increased, but NEVER decreased without destroying / recreating >> the pool. However, increasing the PG Count of a pool is one of >> the most impactful events in a Ceph Cluster, and should be >> avoided for production clusters if possible." >> >> So, in your case, I would consider in adding more OSDs. >> >> Cheers >> Goncalo > > > > _______________________________________________ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com