UNSTABLE: 测试使用多个 Ceph MDS 的动态树分区

快速提示，启用使用多个 Ceph MDS 服务器的动态子树树分区。

如果希望在集群创建期间生效，请编辑您的 ceph.conf

[mds]
mds max =  5

然后重启您的 MDS，它们都会处于活动状态。

或者注入以下命令

bash $ ceph mds set_max_mds 5 max_mds = 5

前后

```bash $ ceph -s

cluster 04c9ddfb-a420-4fac-bbee-997fd182f527
 health HEALTH_OK
 monmap e1: 1 mons at {ceph001=192.168.0.100:6789/0}, election epoch 1, quorum 0 ceph001
 mdsmap e20: 1/1/1 up {0=ceph006=up:active}, 4 up:standby
 osdmap e103: 29 osds: 29 up, 29 in
  pgmap v18261: 1216 pgs, 4 pools, 2145 bytes data, 23 objects
        1237 MB used, 26771 GB / 26773 GB avail
               6 active+clean+replay
            1210 active+clean

$ ceph -s

cluster 04c9ddfb-a420-4fac-bbee-997fd182f527
 health HEALTH_OK
 monmap e1: 1 mons at {ceph001=192.168.0.100:6789/0}, election epoch 1, quorum 0 ceph001
 mdsmap e30: 5/5/5 up {0=ceph006=up:active,1=ceph005=up:active,2=ceph003=up:active,3=ceph002=up:active,4=ceph004=up:active}
 osdmap e103: 29 osds: 29 up, 29 in
  pgmap v18274: 1216 pgs, 4 pools, 5893 bytes data, 85 objects
        1239 MB used, 26771 GB / 26773 GB avail
            1216 active+clean

```

现在使用以下标志启用子树分区

[mds]
mds bal frag = true

有关所有选项。