环境
-
Linux ：centos 7
-
redis：redis-5.0.9
-
集群环境
集群节点（node） 描述 node-01 1主2从 node-02 1主2从 node-03 1主2从
步骤一：在 node-01 中开启集群配置
[root@node-01 redis-5.0.9]# vim 6379redis.conf
daemonize yes #后台运行
cluster-enabled yes #开启集群
cluster-config-file nodes-6379.conf #集群的配置文件（首次启动自动生成）
cluster-node-timeout 15000 #请求超时时长
[root@node-01 redis-5.0.9]# vim 6380redis.conf
daemonize yes
cluster-enabled yes
cluster-config-file nodes-6380.conf
cluster-node-timeout 15000
[root@node-01 redis-5.0.9]# vim 6381redis.conf
daemonize yes
cluster-enabled yes
cluster-config-file nodes-6381.conf
cluster-node-timeout 15000
步骤二：拷贝 node-01 节点 redis 配置到 node-02、node-03
[root@node-01 redis-5.0.9]# scp 6379redis.conf node-02:$PWD
[root@node-01 redis-5.0.9]# scp 6380redis.conf node-02:$PWD
[root@node-01 redis-5.0.9]# scp 6381redis.conf node-02:$PWD
[root@node-01 redis-5.0.9]# scp 6379redis.conf node-03:$PWD
[root@node-01 redis-5.0.9]# scp 6380redis.conf node-03:$PWD
[root@node-01 redis-5.0.9]# scp 6381redis.conf node-03:$PWD
步骤三：分别启动 node-01、node-02、node-03 的 redis 服务器
注：启动 redis 服务器之前要先清除数据，即删除目录里所有
*.aof 文件、 *.rdb 文件 和 nodes-*文件
[root@node-01 redis-5.0.9]# src/redis-server 6379redis.conf
[root@node-01 redis-5.0.9]# src/redis-server 6380redis.conf
[root@node-01 redis-5.0.9]# src/redis-server 6381redis.conf
[root@node-02 redis-5.0.9]# src/redis-server 6379redis.conf
[root@node-02 redis-5.0.9]# src/redis-server 6380redis.conf
[root@node-02 redis-5.0.9]# src/redis-server 6381redis.conf
[root@node-03 redis-5.0.9]# src/redis-server 6379redis.conf
[root@node-03 redis-5.0.9]# src/redis-server 6380redis.conf
[root@node-03 redis-5.0.9]# src/redis-server 6381redis.conf
步骤四：查看 Redis 服务器是否启动成功
[root@node-01 redis-5.0.9]# ps -ef | grep redis
root 1572 1 0 14:39 ? 00:00:00 src/redis-server *:6379 [cluster]
root 1577 1 0 14:40 ? 00:00:00 src/redis-server *:6380 [cluster]
root 1582 1 0 14:40 ? 00:00:00 src/redis-server *:6381 [cluster]
root 1628 1200 0 14:45 pts/0 00:00:00 grep --color=auto redis
[root@node-02 redis-5.0.9]# ps -ef | grep redis
root 1572 1 0 14:39 ? 00:00:00 src/redis-server *:6379 [cluster]
root 1577 1 0 14:40 ? 00:00:00 src/redis-server *:6380 [cluster]
root 1582 1 0 14:40 ? 00:00:00 src/redis-server *:6381 [cluster]
root 1628 1200 0 14:45 pts/0 00:00:00 grep --color=auto redis
[root@node-03 redis-5.0.9]# ps -ef | grep redis
root 1572 1 0 14:39 ? 00:00:00 src/redis-server *:6379 [cluster]
root 1577 1 0 14:40 ? 00:00:00 src/redis-server *:6380 [cluster]
root 1582 1 0 14:40 ? 00:00:00 src/redis-server *:6381 [cluster]
root 1628 1200 0 14:45 pts/0 00:00:00 grep --color=auto redis
以上显示 node-01、node-02 和 node-03 所有的 Redis 服务器都启动成功
步骤五：将 node-01、node-02 和 node-3 的 Redis 服务器部署为集群
[root@node-01 redis-5.0.9]# src/redis-cli --cluster create 192.168.229.21:6379 192.168.229.22:6379 192.168.229.23:6379 192.168.229.21:6380 192.168.229.22:6380 192.168.229.23:6380 192.168.229.21:6381 192.168.229.22:6381 192.168.229.23:6381 --cluster-replicas 2
>>> Performing hash slots allocation on 9 nodes...
# 集群主节点分配槽位
Master[0] -> Slots 0 - 5460 #集群主节点1分配的槽位
Master[1] -> Slots 5461 - 10922 #集群主节点2分配的槽位
Master[2] -> Slots 10923 - 16383 #集群主节点3分配的槽位
# 集群主节点分配从节点
Adding replica 192.168.229.22:6380 to 192.168.229.21:6379
Adding replica 192.168.229.23:6380 to 192.168.229.21:6379
Adding replica 192.168.229.21:6381 to 192.168.229.22:6379
Adding replica 192.168.229.23:6381 to 192.168.229.22:6379
Adding replica 192.168.229.22:6381 to 192.168.229.23:6379
Adding replica 192.168.229.21:6380 to 192.168.229.23:6379
# 集群主节点和从节点列表
M: 00b296e636d06837ecc1f17768b3800c41c2ef7e 192.168.229.21:6379
slots:[0-5460] (5461 slots) master
M: ed5302936686947da2f27346915ddcffd97b4b01 192.168.229.22:6379
slots:[5461-10922] (5462 slots) master
M: 56f2373e93031b1853cc552d2e87b3271137b000 192.168.229.23:6379
slots:[10923-16383] (5461 slots) master
S: 1c1bb17d0ef38a8cf75a60cb18ef56fb44361a79 192.168.229.21:6380
replicates 56f2373e93031b1853cc552d2e87b3271137b000
S: 670f70b2b4360b8c1a09b68cbc61eb26437b0ff0 192.168.229.22:6380
replicates 00b296e636d06837ecc1f17768b3800c41c2ef7e
S: 5a20c0b201dfbc34199bf38bae1ccd3dc20adc6b 192.168.229.23:6380
replicates 00b296e636d06837ecc1f17768b3800c41c2ef7e
S: cebc39c8ee5d8069599c7ae648c658f86a36fe07 192.168.229.21:6381
replicates ed5302936686947da2f27346915ddcffd97b4b01
S: 47c3cfc28913c60f3570f7a8d571d0efb0fcbe4d 192.168.229.22:6381
replicates 56f2373e93031b1853cc552d2e87b3271137b000
S: 1fe5ae70e20f4d333e5e00059fa57f8d57d77f9a 192.168.229.23:6381
replicates ed5302936686947da2f27346915ddcffd97b4b01
Can I set the above configuration? (type 'yes' to accept): yes # 这是输入 yes
>>> Nodes configuration updated
>>> Assign a different config epoch to each node
>>> Sending CLUSTER MEET messages to join the cluster
Waiting for the cluster to join
.......
>>> Performing Cluster Check (using node 192.168.229.21:6379)
M: 00b296e636d06837ecc1f17768b3800c41c2ef7e 192.168.229.21:6379
slots:[0-5460] (5461 slots) master
2 additional replica(s)
S: 5a20c0b201dfbc34199bf38bae1ccd3dc20adc6b 192.168.229.23:6380
slots: (0 slots) slave
replicates 00b296e636d06837ecc1f17768b3800c41c2ef7e
M: 56f2373e93031b1853cc552d2e87b3271137b000 192.168.229.23:6379
slots:[10923-16383] (5461 slots) master
2 additional replica(s)
S: 1c1bb17d0ef38a8cf75a60cb18ef56fb44361a79 192.168.229.21:6380
slots: (0 slots) slave
replicates 56f2373e93031b1853cc552d2e87b3271137b000
M: ed5302936686947da2f27346915ddcffd97b4b01 192.168.229.22:6379
slots:[5461-10922] (5462 slots) master
2 additional replica(s)
S: cebc39c8ee5d8069599c7ae648c658f86a36fe07 192.168.229.21:6381
slots: (0 slots) slave
replicates ed5302936686947da2f27346915ddcffd97b4b01
S: 1fe5ae70e20f4d333e5e00059fa57f8d57d77f9a 192.168.229.23:6381
slots: (0 slots) slave
replicates ed5302936686947da2f27346915ddcffd97b4b01
S: 47c3cfc28913c60f3570f7a8d571d0efb0fcbe4d 192.168.229.22:6381
slots: (0 slots) slave
replicates 56f2373e93031b1853cc552d2e87b3271137b000
S: 670f70b2b4360b8c1a09b68cbc61eb26437b0ff0 192.168.229.22:6380
slots: (0 slots) slave
replicates 00b296e636d06837ecc1f17768b3800c41c2ef7e
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
- --cluster create：表示创建集群节点
- --cluster-replicas 2：表示为集群中的主节点创建 2 个从节点
步骤六：启动Redis 客户端连接集群主节点
-c ：表示连接集群
-h：表示集群的主节点IP地址
-p：表示集群的主节点端口号
[root@node-01 redis-5.0.9]# src/redis-cli -c -h 192.168.229.21 -p 6379 # redis 客户端连接集群主节点
192.168.229.22:6379> cluster info #查看集群信息
cluster_state:ok
cluster_slots_assigned:16384
cluster_slots_ok:16384
cluster_slots_pfail:0
cluster_slots_fail:0
cluster_known_nodes:9
cluster_size:3
cluster_current_epoch:12
cluster_my_epoch:1
cluster_stats_messages_ping_sent:6633
cluster_stats_messages_pong_sent:2231
cluster_stats_messages_meet_sent:2
cluster_stats_messages_sent:8866
cluster_stats_messages_ping_received:2225
cluster_stats_messages_pong_received:2207
cluster_stats_messages_meet_received:6
cluster_stats_messages_fail_received:2
cluster_stats_messages_auth-req_received:3
cluster_stats_messages_received:4443
192.168.229.21:6379> cluster nodes # 查看集群中各节点信息
192.168.229.22:6379@16379 myself,master - 0 1615900052000 2 connected 5461-10922 #集群主节点
192.168.229.21:6379@16379 master - 0 1615900058000 1 connected 0-5460 #集群主节点
192.168.229.22:6380@16380 slave 0 1615900055542 5 connected
192.168.229.23:6380@16380 slave 0 1615900059581 6 connected
192.168.229.23:6379@16379 master - 0 1615900057559 3 connected 10923-16383 #集群主节点
192.168.229.23:6381@16381 slave 0 1615900060594 9 connected
192.168.229.22:6381@16381 slave 0 1615900058569 8 connected
192.168.229.21:6380@16380 slave 0 1615900057000 4 connected
192.168.229.21:6381@16381 slave 0 1615900059000 7 connected
步骤七：集群环境测试
连接集群 node-01 主节点，并添加数据如下：
192.168.229.21:6379> set name zhangsan
-> Redirected to slot [5798] located at 192.168.229.22:6379
OK
192.168.229.22:6379> get name
"zhangsan"
可以看到，数据并没有存储到 node-01 的主节点上，而是数据存储在 node-02 的主节点上，而且 Redis 客户端也自动从node-01 转到了 node-02。
为何数据存储到 node-02 上，而不是 node-01 呢，原因是集群为数据分配的槽位是 slot [5798]，node-02 的槽位范围为 5461 - 10922，当然应该存储在 node-02 节点上。
我们到 node-02 节点上查看数据，如下：
192.168.229.22:6379> get name
"zhangsan"
步骤八：集群故障转移测试
为了触发故障转移，我们可以做的最简单的事情（也就是在分布式系统中可能出现的语义上最简单的故障）是使单个进程崩溃。
也可以直接 shutdown 关闭 redis 服务器
[root@node-01 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6379 debug segfault
Error: Server closed the connection
可以看到，node-02 主节点被我们搞崩溃了，这时查看集群节点状态，如下：
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6380
192.168.229.22:6380> cluster nodes
192.168.229.23:6379@16379 master - 0 1615900421261 3 connected 10923-16383
192.168.229.22:6379@16379 master,fail - 16159003931 2 disconnected 5461-10922 # node-02:6379已故障下线
192.168.229.21:6381@16381 slave 0 1615900419000 7 connected
192.168.229.23:6381@16381 slave 0 1615900419236 9 connected
192.168.229.21:6380@16380 slave 0 1615900420247 4 connected
192.168.229.22:6380@16380 myself,slave 0 1615900417000 5 connected # node-02:6380 升级为新的主节点
192.168.229.23:6380@16380 slave 0 1615900420000 6 connected
192.168.229.22:6381@16381 slave 0 1615900417000 8 connected
192.168.229.21:6379@16379 master - 0 1615900417212 1 connected 0-5460
以上结果显示，故障转移成功，node-02:6380 升级为新的主节点。现在，再将 node-02:6379 重启，如下：
[root@node-02 redis-5.0.9]# src/redis-server 6379redis.conf
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6380
192.168.229.22:6380> cluster nodes
192.168.229.23:6379@16379 master - 0 1615900858050 3 connected 10923-16383
192.168.229.22:6379@16379 slave 0 1615900856026 12 connected #降为从节点
192.168.229.21:6381@16381 slave 0 1615900857040 12 connected
192.168.229.23:6381@16381 master - 0 1615900855019 12 connected 5461-10922
192.168.229.21:6380@16380 slave 0 1615900856000 4 connected
192.168.229.22:6380@16380 myself,slave 0 1615900855000 5 connected
192.168.229.23:6380@16380 slave 0 1615900855000 6 connected
192.168.229.22:6381@16381 slave 0 1615900854005 8 connected
192.168.229.21:6379@16379 master - 0 1615900854000 1 connected 0-5460
以上结果显示，重启后原集群主节点已变为从节点。至此，集群环境搭建成功：）
步骤九：关闭集群
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.21 -p 6381 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.21 -p 6380 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.21 -p 6379 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6381 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6380 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.22 -p 6379 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.23 -p 6381 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.23 -p 6380 shutdown
[root@node-02 redis-5.0.9]# src/redis-cli -c -h 192.168.229.23 -p 6379 shutdown