Hello, I am playing around with a test ceph 14.2.20 cluster. The cluster consists of 4 VMs, each VM has 2 OSDs. The first three VMs vceph1, vceph2 and vceph3 are monitors. vceph1 is also mgr. What I did was quite simple. The cluster is in the state HEALTHY: vceph2: systemctl stop ceph-osd@2 # let ceph repair until ceph -s reports cluster is healthy again vceph2: systemctl start ceph-osd@2 # @ 15:39:15, for the logs # cluster reports in cephs -s that 8 OSDs are up and in, then # starts rebalance osd.2 vceph2: ceph -s # hangs forever also if executed on vceph3 or 4 # mon on vceph1 eats 100% CPU permanently, the other mons ~0 %CPU vceph1: systemctl stop ceph-mon@vceph1 # wait ~30 sec to terminate vceph1: systemctl start ceph-mon@vceph1 # Everything is OK again I posted the mon-log to: https://cloud.uni-koblenz.de/s/t8tWjWFAobZb5Hy Strange enough if I set "debug mon 20" before starting the experiment this bug does not show up. I also tried the very same procedure on the same cluster updated to 15.2.11 but I was unable to reproduce this bug in this ceph version. Thanks Rainer -- Rainer Krienke, Uni Koblenz, Rechenzentrum, A22, Universitaetsstrasse 1 56070 Koblenz, Web: http://www.uni-koblenz.de/~krienke, Tel: +49261287 1312 PGP: http://www.uni-koblenz.de/~krienke/mypgp.html, Fax: +49261287 1001312