Redis集群搭建

安装Redis集群准备

采用原生搭建的方式搭建3主3从的Redis Cluster，分别给3个master节点配置一个slave节点，总计6个Redis节点。
但由于我们只有4台机器，所以选择在其中的两台机器上安装两个redis。

安装步骤参考之前写的文章

修改配置文件

port 6380 # server端口，4台server用默认的6379，所以无需修改，另外两台则改成6380。
# bind 127.0.0.1 //这一行要注释，否则无法远程连接
cluster-enabled yes
cluster-config-file nodes.conf //node.conf文件不用管。
cluster-node-timeout 5000
appendonly yes //aof
daemonize yes 
protected-mode no

启动服务

[root@localhost]# redis-server redis.conf

到这里我们就有以集群模式启动的6台redis server，但是每台服务器还没有进行slot指派,此时是不能对外提供服务的。

开放防火墙端口

[root@test-3]# firewall-cmd --zone=public --add-port={6379/tcp,16379/tcp} --permanent
[root@test-3]# firewall-cmd --reload

搭建集群（slot指派）

用redis官方提供的redis-cli 命令的--cluster选项。
下面的命令将六台服务器组成一个集群
其中复制因子为1所,以会有3台master,另外3台为slave。
16384个slot会尽可能均匀的指派给3台master, 而3台slave异步的从其master进行复制。
任选一台机执行以下命令

[root@test-3 redis-6.2.5]# src/redis-cli --cluster create 192.168.0.129:6379 192.168.0.250:6379 test-3:6379 test-3:6380 test-4:6379 test-4:6380 --cluster-replicas 1
>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica test-3:6380 to 192.168.0.129:6379
Adding replica test-4:6380 to 192.168.0.250:6379
Adding replica test-4:6379 to sz-cms-3:6379
M: ae80cca550b15585b20b4ac7511f7751437f6ee 192.168.0.129:6379
   slots:[0-5460] (5461 slots) master
M: d7ca9360b74b777e7739e05d2265b6c4d5f5ca0 192.168.0.250:6379
   slots:[5461-10922] (5462 slots) master
M: 68569ee4c6bb4b60981ea34ee1b7c61b2ce285 test-3:6379
   slots:[10923-16383] (5461 slots) master
S: 3532972c73ce3b785d538983f725486e7a0fc9 test-3:6380
   replicates ae80cca550b558b20b4acc7511f7751437f6ee
S: b648cc92b55d07ec638c7d41a9ca24fc5d9160 test-4:6379
   replicates 68569ee4cbb4b609881e7a34ee1b7c61b2ce285
S: 25e9b9a3de4ac4c3e47eb3fdb9f8e80c98e728f test-4:6380
   replicates d7ca9360b74b777e773905d2265b6c4d5f5ca0
Can I set the above configuration? (type 'yes' to accept): 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 192.168.0.129:6379)
M: ae80cca550b185b20b4acc7511f7751437f6ee 192.168.0.129:6379
   slots:[0-5460] (5461 slots) master
   1 additional replica(s)
M: d7ca9360b74b777e77397e05d25b6c4d5f5ca0 192.168.0.250:6379
   slots:[5461-10922] (5462 slots) master
   1 additional replica(s)
S: 25e9b9a3de4c4c3e47b3fdb9f8e80c98e728f 192.168.0.141:6380
   slots: (0 slots) slave
   replicates d7ca9360b74b77e7739705d2265b6c4d5f5ca0
M: 68569ee4c6bb4609881e7a34ee1b7c1b2ce285 192.168.0.228:6379
   slots:[10923-16383] (5461 slots) master
   1 additional replica(s)
S: b648cc92b55d17ec638c7d41ca9a24fc5d9160 192.168.0.141:6379
   slots: (0 slots) slave
   replicates 68569ee4c6bbb609881e7a4ee1b7c612ce285
S: 3532972c3ce3b785d5389783f72546e7a0fc9 192.168.0.228:6380
   slots: (0 slots) slave
   replicates ae8ca550b5585b20b4cc7511f7751437f6ee
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.

踩坑

一开始执行的命令中我全部用hostname，但出现以下错误

(error) ERR Invalid node address specified: test-1:6379

网上找到原因说好像不支持hostname，于是改成使用ip，然后就可以正常运行了。

查看集群情况

[root@test-3 redis-6.2.5]# src/redis-cli 
127.0.0.1:6379> cluster nodes
3532972c7ce3b7885d38783f725486e7a0fc9 192.168.0.228:6380@16380 slave ae80cc550b1558b20b4acc7511f77514376ee 0 1629874202654 1 connected
25eb9ade4ac4c3478eb3fdb98e80c9e728f 192.168.0.141:6380@16380 slave d7ca930b74b77777397e0d2265b6cd5f5ca0 0 1629874204664 2 connected
d7ca9360b7b777e7797e05d265b64d5f5ca0 192.168.0.250:6379@16379 master - 0 1629874205000 2 connected 5461-10922
ae8cca550b15585b0b4acc751f7751437f6ee 192.168.0.129:6379@16379 master - 0 1629874206673 1 connected 0-5460
68569ee4c6b4b609881e7a3ee1b761b2ce285 192.168.0.228:6379@16379 myself,master - 0 1629874206000 3 connected 10923-16383
b648c92b55d017ec68c7d41ca9c24fc5d9160 192.168.0.141:6379@16379 slave 6856ee4c6b4b609881e734ee17c61b2ce285 0 1629874206000 3 connected

添加密码

每个节点都需要自己上去设置。然后因为有两个节点使用了6380端口，所以命令里需要加入-p 6380，其他节点用默认的即可。

[root@test-3 redis-replica]# src/redis-cli -p 6380
127.0.0.1:6380> config set masterauth 123456
OK
127.0.0.1:6380> config set requirepass 123456
OK
127.0.0.1:6380> config rewrite
OK