MDS多活配置

默认情况下，cephfs文件系统只配置一个活跃的mds进程。在大型系统中，为了扩展元数据性能，可以配置多个活跃的mds进程，此时他们会共同承担元数据负载。

要配置mds多活，只需要修改cephfs系统的max_mds参数即可。以下是未配置之前的集群状态

[root@test1 ~]# ceph -s  cluster:    id:     94e1228c-caba-4eb5-af86-259876a44c28    health: HEALTH_OK   services:    mon: 3 daemons, quorum test1,test2,test3    mgr: test1(active), standbys: test3, test2    mds: cephfs-2/2/1 up  {0=test2=up:active,1=test3=up:active}, 1 up:standby    osd: 18 osds: 18 up, 18 in    rgw: 3 daemons active   data:    pools:   8 pools, 400 pgs    objects: 305 objects, 3.04MiB    usage:   18.4GiB used, 7.84TiB / 7.86TiB avail    pgs:     400 active+clean

1、配置多活

[root@test1 ~]# ceph mds set max_mds 2[root@test1 ~]# ceph -s  cluster:    id:     94e1228c-caba-4eb5-af86-259876a44c28    health: HEALTH_OK   services:    mon: 3 daemons, quorum test1,test2,test3    mgr: test1(active), standbys: test3, test2    mds: cephfs-2/2/2 up  {0=test2=up:active,1=test3=up:active}, 1 up:standby    osd: 18 osds: 18 up, 18 in    rgw: 3 daemons active   data:    pools:   8 pools, 400 pgs    objects: 305 objects, 3.04MiB    usage:   18.4GiB used, 7.84TiB / 7.86TiB avail    pgs:     400 active+clean

2、恢复单活mds

[root@test1 ~]# ceph mds set max_mds 1[root@test1 ~]# ceph mds deactivate 1[root@test1 ~]# ceph -s  cluster:    id:     94e1228c-caba-4eb5-af86-259876a44c28    health: HEALTH_OK   services:    mon: 3 daemons, quorum test1,test2,test3    mgr: test1(active), standbys: test3, test2    mds: cephfs-1/1/1 up  {0=test2=up:active}, 2 up:standby    osd: 18 osds: 18 up, 18 in    rgw: 3 daemons active   data:    pools:   8 pools, 400 pgs    objects: 305 objects, 3.04MiB    usage:   18.4GiB used, 7.84TiB / 7.86TiB avail    pgs:     400 active+clean   io:    client:   31.7KiB/s rd, 170B/s wr, 31op/s rd, 21op/s wr