ceph version 14.2.4 (75f4de193b3ea58512f204623e6c5a16e6c1e1ba) nautilus (stable) os :CentOS Linux release 7.7.1908 (Core) single node ceph cluster with 1 mon,1mgr,1 mds,1rgw and 12osds , but only cephfs is used. ceph -s is blocked after shutting down the machine (192.168.0.104), then ip address changed to 192.168.1.6 I created the monmap with monmap tool and update the ceph.conf , hosts file and then start ceph-mon. and the ceph-mon log: ... 2019-12-11 08:57:45.170 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1285.14s 2019-12-11 08:57:50.170 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1290.14s 2019-12-11 08:57:55.171 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1295.14s 2019-12-11 08:58:00.171 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1300.14s 2019-12-11 08:58:05.172 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1305.14s 2019-12-11 08:58:10.171 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1310.14s 2019-12-11 08:58:15.173 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1315.14s 2019-12-11 08:58:20.173 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1320.14s 2019-12-11 08:58:25.174 7f952cdac700 1 mon.ceph-node1 at 0(leader).mds e34 no beacon from mds.0.10 (gid: 4384 addr: [v2:192.168.0.104:6898/4084823750,v1:192.168.0.104:6899/4084823750] state: up:active) since 1325.14s ... I changed IP back to 192.168.0.104 yeasterday, but all the same. # cat /etc/ceph/ceph.conf [client.libvirt] admin socket = /var/run/ceph/$cluster-$type.$id.$pid.$cctid.asok # must be writable by QEMU and allowed by SELinux or AppArmor log file = /var/log/ceph/qemu-guest-$pid.log # must be writable by QEMU and allowed by SELinux or AppArmor [client.rgw.ceph-node1.rgw0] host = ceph-node1 keyring = /var/lib/ceph/radosgw/ceph-rgw.ceph-node1.rgw0/keyring log file = /var/log/ceph/ceph-rgw-ceph-node1.rgw0.log rgw frontends = beast endpoint=192.168.1.6:8080 rgw thread pool size = 512 # Please do not change this file directly since it is managed by Ansible and will be overwritten [global] cluster network = 192.168.1.0/24 fsid = e384e8e6-94d5-4812-bfbb-d1b0468bdef5 mon host = [v2:192.168.1.6:3300,v1:192.168.1.6:6789] mon initial members = ceph-node1 osd crush chooseleaf type = 0 osd pool default crush rule = -1 public network = 192.168.1.0/24 [osd] osd memory target = 7870655146