② ceph集群中添加或移除主机

	1.查看现有的集群主机列表
[root@ceph141 ~]# ceph orch host ls
HOST     ADDR        LABELS  STATUS  
ceph141  10.0.0.141  _admin          
1 hosts in cluster
[root@ceph141 ~]# 

	2.把秘钥放到其他服务器上
[root@ceph141 ~]# ssh-copy-id -f -i /etc/ceph/ceph.pub ceph142
[root@ceph141 ~]# ssh-copy-id -f -i /etc/ceph/ceph.pub ceph143

	3.添加节点加入到集群
[root@ceph141 ~]# ceph orch host add ceph142 10.0.0.142
Added host 'ceph142' with addr '10.0.0.142'
[root@ceph141 ~]# 
[root@ceph141 ~]# ceph orch host add ceph143 10.0.0.143
Added host 'ceph143' with addr '10.0.0.143'
[root@ceph141 ~]# 


温馨提示：
	将集群加入成功后，会自动创建"/var/lib/ceph/<Ceph_Cluster_ID>"相关数据目录。


	4.再次查看集群的主机列表
[root@ceph141 ~]# ceph orch host ls
HOST     ADDR        LABELS  STATUS  
ceph141  10.0.0.141  _admin          
ceph142  10.0.0.142                  
ceph143  10.0.0.143                  
3 hosts in cluster
[root@ceph141 ~]#  

温馨提示:
	当然，也可以通过查看WebUI观察ceph集群有多少个主机。
https://ceph141:8443/#/hosts


	5.移除主机【选做，如果将来真有这个需求在操作】
[root@ceph141 ~]# ceph orch host rm ceph143
Removed  host 'ceph143'
[root@ceph141 ~]# 
[root@ceph141 ~]# ceph orch host ls
HOST     ADDR        LABELS  STATUS  
ceph141  10.0.0.141  _admin          
ceph142  10.0.0.142                  
2 hosts in cluster
[root@ceph141 ~]# 
[root@ceph141 ~]# 
[root@ceph141 ~]# ceph orch host add ceph143 10.0.0.143  # 为了实验效果，我还是将ceph143加回来
Added host 'ceph143' with addr '10.0.0.143'
[root@ceph141 ~]# 
[root@ceph141 ~]# ceph orch host ls
HOST     ADDR        LABELS  STATUS  
ceph141  10.0.0.141  _admin          
ceph142  10.0.0.142                  
ceph143  10.0.0.143                  
3 hosts in cluster
[root@ceph141 ~]#