接下来，我们使用 redis-cli 连接并测试一下集群的运行状态，代码如下：
$ redis-cli -c -p 30001 # 连接到集群 127.0.0.1:30001> cluster info # 查看集群信息 cluster_state:ok # 状态正常 cluster_slots_assigned:16384 # 槽位数 cluster_slots_ok:16384 # 正常的槽位数 cluster_slots_pfail:0 cluster_slots_fail:0 cluster_known_nodes:6 # 集群的节点数 cluster_size:3 # 集群主节点数 cluster_current_epoch:6 cluster_my_epoch:1 cluster_stats_messages_ping_sent:130 cluster_stats_messages_pong_sent:127 cluster_stats_messages_sent:257 cluster_stats_messages_ping_received:122 cluster_stats_messages_pong_received:130 cluster_stats_messages_meet_received:5 cluster_stats_messages_received:257 复制代码相关字段的说明已经标识在上述的代码中了，这里就不再赘述。
动态增删节点某些情况下，我们需要根据实际的业务情况，对已经在运行的集群进行动态的添加或删除节点，那我们就需要进行以下操作。
1.增加主节点 添加方式一：cluster meet使用 cluster meet ip:port 命令就可以把一个节点加入到集群中，执行命令如下：
127.0.0.1:30001> cluster meet 127.0.0.1 30007 OK 127.0.0.1:30001> cluster nodes dc0702625743c48c75ea935c87813c4060547cef 127.0.0.1:30006@40006 slave 3da35c40c43b457a113b539259f17e7ed616d13d 0 1585142916000 6 connected df0190853a53d8e078205d0e2fa56046f20362a7 127.0.0.1:30007@40007 master - 0 1585142917740 0 connected f5958382af41d4e1f5b0217c1413fe19f390b55f 127.0.0.1:30003@40003 master - 0 1585142916738 3 connected 10923-16383 3da35c40c43b457a113b539259f17e7ed616d13d 127.0.0.1:30002@40002 master - 0 1585142913000 2 connected 5461-10922 abec9f98f9c01208ba77346959bc35e8e274b6a3 127.0.0.1:30005@40005 slave 887397e6fefe8ad19ea7569e99f5eb8a803e3785 0 1585142917000 5 connected 887397e6fefe8ad19ea7569e99f5eb8a803e3785 127.0.0.1:30001@40001 myself,master - 0 1585142915000 1 connected 0-5460 1a324d828430f61be6eaca7eb2a90728dd5049de 127.0.0.1:30004@40004 slave f5958382af41d4e1f5b0217c1413fe19f390b55f 0 1585142916000 4 connected 复制代码可以看出端口为 30007 的节点并加入到集群中，并设置成了主节点。
添加方式二：add-node使用 redis-cli --cluster add-node 添加节点ip:port 集群某节点ip:port 也可以把一个节点添加到集群中，执行命令如下：
$ redis-cli --cluster add-node 127.0.0.1:30008 127.0.0.1:30001 >>> Adding node 127.0.0.1:30008 to cluster 127.0.0.1:30001 >>> Performing Cluster Check (using node 127.0.0.1:30001) M: 887397e6fefe8ad19ea7569e99f5eb8a803e3785 127.0.0.1:30001 slots:[0-5460] (5461 slots) master 1 additional replica(s) S: dc0702625743c48c75ea935c87813c4060547cef 127.0.0.1:30006 slots: (0 slots) slave replicates 3da35c40c43b457a113b539259f17e7ed616d13d M: df0190853a53d8e078205d0e2fa56046f20362a7 127.0.0.1:30007 slots: (0 slots) master M: f5958382af41d4e1f5b0217c1413fe19f390b55f 127.0.0.1:30003 slots:[10923-16383] (5461 slots) master 1 additional replica(s) M: 1d09d26fd755298709efe60278457eaa09cefc26 127.0.0.1:30008 slots: (0 slots) master M: 3da35c40c43b457a113b539259f17e7ed616d13d 127.0.0.1:30002 slots:[5461-10922] (5462 slots) master 1 additional replica(s) S: abec9f98f9c01208ba77346959bc35e8e274b6a3 127.0.0.1:30005 slots: (0 slots) slave replicates 887397e6fefe8ad19ea7569e99f5eb8a803e3785 S: 1a324d828430f61be6eaca7eb2a90728dd5049de 127.0.0.1:30004 slots: (0 slots) slave replicates f5958382af41d4e1f5b0217c1413fe19f390b55f [OK] All nodes agree about slots configuration. >>> Check for open slots... >>> Check slots coverage... [OK] All 16384 slots covered. [ERR] Node 127.0.0.1:30008 is not empty. Either the node already knows other nodes (check with CLUSTER NODES) or contains some key in database 0. 复制代码从以上结果可以看出 30008 节点也被设置成了主节点。
2.添加从节点