搭建集群

　　之前搭建redis集群可以采用redis-trib.rb，它是采用ruby实现的redis集群管理工具，内部通过cluster 相关命令帮我们简化集群创建，检查，槽迁移和均衡等常见运维操作，使用之前需要安装ruby依赖环境，但是在我目前的redis版本中，redis-trib.rb工具已经被整合到redis-cli命令中了。　

[root@redis src]# redis-cli --version
redis-cli 6.2.6
[root@redis src]# redis-server --version
Redis server v=6.2.6 sha=00000000:0 malloc=jemalloc-5.1.0 bits=64 build=dbb063e6f0357f98

　　因此下面将会用redis-cli 命令快速搭建redis集群

├── 6379
│   ├── conf
│   │   └── redis-6379.conf
│   ├── data
│   └── log
├── 6380
│   ├── conf
│   │   └── redis-6380.conf
│   ├── data
│   └── log
├── 6381
│   ├── conf
│   │   └── redis-6381.conf
│   ├── data
│   └── log
├── 6382
│   ├── conf
│   │   └── redis-6382.conf
│   ├── data
│   └── log
├── 6383
│   ├── conf
│   │   └── redis-6383.conf
│   ├── data
│   └── log
└── 6384
    ├── conf
    │   └── redis-6384.conf
    ├── data
    │   └── dump.rdb
    └── log

　　这里相对于上一节的配置中在redis-{port}.conf加入了appendonly yes 持久化参数。

　　先启动每个redis数据节点　　

[root@redis data]# redis-server /data/6379/conf/redis-6379.conf 
[root@redis data]# redis-server /data/6380/conf/redis-6380.conf 
[root@redis data]# redis-server /data/6381/conf/redis-6381.conf 
[root@redis data]# redis-server /data/6382/conf/redis-6382.conf 
[root@redis data]# redis-server /data/6383/conf/redis-6383.conf 
[root@redis data]# redis-server /data/6384/conf/redis-6384.conf 
[root@redis data]# ps -ef|grep redis
root      10906   6097  0 08:05 pts/1    00:00:00 redis-cli -p 6379
root      10924   5723  0 08:23 pts/0    00:00:00 redis-cli -p 6384
root      11309      1  0 09:28 ?        00:00:00 redis-server *:6379 [cluster]
root      11315      1  0 09:28 ?        00:00:00 redis-server *:6380 [cluster]
root      11321      1  0 09:29 ?        00:00:00 redis-server *:6381 [cluster]
root      11327      1  0 09:29 ?        00:00:00 redis-server *:6382 [cluster]
root      11333      1  0 09:29 ?        00:00:00 redis-server *:6383 [cluster]
root      11339      1  0 09:29 ?        00:00:00 redis-server *:6384 [cluster]

　 将这些单节点的redis组成一个redis集群　　

[root@redis 6379]# redis-cli --cluster create  127.0.0.1:6379 127.0.0.1:6380 127.0.0.1:6381 127.0.0.1:6382 127.0.0.1:6383 127.0.0.1:6384 --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 127.0.0.1:6383 to 127.0.0.1:6379
Adding replica 127.0.0.1:6384 to 127.0.0.1:6380
Adding replica 127.0.0.1:6382 to 127.0.0.1:6381
>>> Trying to optimize slaves allocation for anti-affinity
[WARNING] Some slaves are in the same host as their master
M: f87d0bac225f13d1d16e6f5cffecff3b83998484 127.0.0.1:6379
   slots:[0-5460] (5461 slots) master
M: 78f13905a498d20450033f04014f905193b251c0 127.0.0.1:6380
   slots:[5461-10922] (5462 slots) master
M: 39276f17bb64869a1b4c03433bde1f688a2065e9 127.0.0.1:6381
   slots:[10923-16383] (5461 slots) master
S: 9b9c5a435fb8fa59d978a98be0e0aeaedb5027d5 127.0.0.1:6382
   replicates 78f13905a498d20450033f04014f905193b251c0
S: da69fbf33f9395f4d9ed3016e69855b7fbb28f62 127.0.0.1:6383
   replicates 39276f17bb64869a1b4c03433bde1f688a2065e9
S: 889af758c59d392240d2d2d38e37c9df7be053ab 127.0.0.1:6384
   replicates f87d0bac225f13d1d16e6f5cffecff3b83998484
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 127.0.0.1:6379)
M: f87d0bac225f13d1d16e6f5cffecff3b83998484 127.0.0.1:6379
   slots:[0-5460] (5461 slots) master
   1 additional replica(s)
M: 39276f17bb64869a1b4c03433bde1f688a2065e9 127.0.0.1:6381
   slots:[10923-16383] (5461 slots) master
   1 additional replica(s)
S: 889af758c59d392240d2d2d38e37c9df7be053ab 127.0.0.1:6384
   slots: (0 slots) slave
   replicates f87d0bac225f13d1d16e6f5cffecff3b83998484
S: 9b9c5a435fb8fa59d978a98be0e0aeaedb5027d5 127.0.0.1:6382
   slots: (0 slots) slave
   replicates 78f13905a498d20450033f04014f905193b251c0
S: da69fbf33f9395f4d9ed3016e69855b7fbb28f62 127.0.0.1:6383
   slots: (0 slots) slave
   replicates 39276f17bb64869a1b4c03433bde1f688a2065e9
M: 78f13905a498d20450033f04014f905193b251c0 127.0.0.1:6380
   slots:[5461-10922] (5462 slots) master
   1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.

　　进单点进去查看

127.0.0.1:6379> cluster nodes
39276f17bb64869a1b4c03433bde1f688a2065e9 127.0.0.1:6381@16381 master - 0 1648345208000 3 connected 10923-16383
889af758c59d392240d2d2d38e37c9df7be053ab 127.0.0.1:6384@16384 slave f87d0bac225f13d1d16e6f5cffecff3b83998484 0 1648345207916 1 connected
9b9c5a435fb8fa59d978a98be0e0aeaedb5027d5 127.0.0.1:6382@16382 slave 78f13905a498d20450033f04014f905193b251c0 0 1648345209947 2 connected
da69fbf33f9395f4d9ed3016e69855b7fbb28f62 127.0.0.1:6383@16383 slave 39276f17bb64869a1b4c03433bde1f688a2065e9 0 1648345209000 3 connected
78f13905a498d20450033f04014f905193b251c0 127.0.0.1:6380@16380 master - 0 1648345209000 2 connected 5461-10922
f87d0bac225f13d1d16e6f5cffecff3b83998484 127.0.0.1:6379@16379 myself,master - 0 1648345207000 1 connected 0-5460

　　将上面的显示的redis-cluster是搭建成功了。。。

集群完整性检查

　　集群完整性指所有的槽都分配到存活的主节点上，只要16384个槽有一个没有分配给节点则表示集群不不完整。可以使用check命令进行检查：

[root@redis 6379]# redis-cli --cluster check -h 127.0.0.1 -p 6379
[ERR] Wrong number of arguments for specified --cluster sub command
[root@redis 6379]# 
[root@redis 6379]# redis-cli --cluster check  127.0.0.1:6379
127.0.0.1:6379 (f87d0bac...) -> 0 keys | 5461 slots | 1 slaves.
127.0.0.1:6381 (39276f17...) -> 0 keys | 5461 slots | 1 slaves.
127.0.0.1:6380 (78f13905...) -> 0 keys | 5462 slots | 1 slaves.
[OK] 0 keys in 3 masters.
0.00 keys per slot on average.
>>> Performing Cluster Check (using node 127.0.0.1:6379)
M: f87d0bac225f13d1d16e6f5cffecff3b83998484 127.0.0.1:6379
   slots:[0-5460] (5461 slots) master
   1 additional replica(s)
M: 39276f17bb64869a1b4c03433bde1f688a2065e9 127.0.0.1:6381
   slots:[10923-16383] (5461 slots) master
   1 additional replica(s)
S: 889af758c59d392240d2d2d38e37c9df7be053ab 127.0.0.1:6384
   slots: (0 slots) slave
   replicates f87d0bac225f13d1d16e6f5cffecff3b83998484
S: 9b9c5a435fb8fa59d978a98be0e0aeaedb5027d5 127.0.0.1:6382
   slots: (0 slots) slave
   replicates 78f13905a498d20450033f04014f905193b251c0
S: da69fbf33f9395f4d9ed3016e69855b7fbb28f62 127.0.0.1:6383
   slots: (0 slots) slave
   replicates 39276f17bb64869a1b4c03433bde1f688a2065e9
M: 78f13905a498d20450033f04014f905193b251c0 127.0.0.1:6380
   slots:[5461-10922] (5462 slots) master
   1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.

　　可以看到，提示集群所有的槽都已经分配到节点上。

　　大功告成。。。是不是很简单