Servers: 6 (include 7osds) total 42osdsl OS: Centos7 Ceph: 10.2.5 Hi, everyone The cluster is used for VM image storage and object storage. And I have a bucket which has more than 20 million objects. Now, I have a problem that cluster blocks operation. Suddenly cluster blocked operations, then VMs can't read disk. After a few hours, osd.1 was down. There is no disk fail messages in dmesg. And no error is in smartctl -a /dev/sde. I tried to wake up osd.1, but osd.1 is down soon. Just after re-waking up osd.1, VM can access to the disk. But osd.1 always uses 100% CPU, then cluster marked osd.1 down and the osd was dead by suicide timeout. I found that the osdmap epoch of osd.1 is different from other one. So I think osd.1 was dead. Question. (1) Why does the epoch of osd.1 differ from other osds ones ? I checked all osds oldest_map and newest_map by ~ceph daemon osd.X status~ All osd's ecpoch are same number except osd.1 (2) Why does osd.1 use CPU full? After the cluster marked osd.1 down, osd.1 keeps up busy. When I execute "ceph tell osd.1 injectargs --debug-ms 5/1", osd.1 doesn't answer. Thank you. -- Makito