Redis Cluster 原理探讨

Redis Cluster

hash(key) % 16384 = slot 哈希槽 = hash(key) & 2^n^

slot - hash槽分布范围[0-5460] 、 [5461-10922]、[10923-16383]

# 创建RedisCluster配置的节点目录
[root@redis]$ mkdir -p rediscluster/node800{1,2,3,4,5,6}
# 复制Redis配置到每个节点目录
[root@redis]$ cp redis-5.0.2/redis.conf rediscluster/node8001/
# 修改节点配置
[root@redis]$ vim rediscluster/node8001/redis.conf
# 批量修改
:%s/8001/8002/g

# 启动集群配置
[root@redis]$ redis-server rediscluster/800*/redis.conf
# 校验启动情况
[root@reids]$ ps -ef | grep redis
# 集群命令帮助
[root@redis]$ redis-cli --cluster help
# 创建集群关系
[root@redis]$ redis-cli -a 111111 --cluster create --cluster-replicas 1 192.168.109.200:8001 192.168.109.200:8002 192.168.109.200:8003 192.168.109.200:8004 192.168.109.200:8005 192.168.109.200:8006  


# 连接任意一个节点客户端[带-c说明是集群方式 智能客户端]
[root@redis]$ redis-cli -a 111111 -c -h 192.168.109.200 -p 8001
# 验证集群信息
> cluster info 
> cluster nodes
> cluster slots

序号	配置项	选项	释义
1	cluster-enabled	yes	启动集群模式
2	port	8001	端口
3	dir	/usr/local/redis-cluster/8001/	指定数据目录，绝对目录
4	cluster-config-file	nodes-8001.conf	集群节点信息，hash crc16
5	cluster-node-timeout	5000	集群节点超时时间,心跳时间
6	bind	#127.0.0.1	测试需要注释掉，生产需指定配置
7	protected-mode	no	关闭保护模式
8	requirepass	111111	redis访问密码
9	masterauth	111111	集群节点间的访问密码，与上述保持一致
10	damonize	yes	后台启动
11	appendonly	yes

Laravel 框架使用redis cluster需要修改的地方

# .composer.lock
# ...
"require": {
    # ...
    "php": "^7.1.3",
    "predis/predis": "^1.1",
    # 如果安装horizon，请注意Redis密码必设且相同
    # config/horizon.php中'use'=>'horizon'
    # ...
},
# ...


# .env
# ...
CACHE_DRIVER=redis
# ...
    
# cache.php
# ...
'redis' => [
    'driver'     => 'redis',
    'connection' => 'default',
],
#...


# database.php
# ...
'redis' => [
    'client'  => env('REDIS_CLIENT', 'predis'),
    'options' => [
        'cluster' => env('REDIS_CLUSTER', 'redis'),
    ],
    'clusters' => [
        'default' => [
            [
                'host'     => env('REDIS_HOST_A'),
                'password' => env('REDIS_PASSWORD_A'),
                'port'     => env('REDIS_PORT_A', 6379),
                'database' => env('REDIS_DB_A', 0),
            ],
            [
                'host'	   => env('REDIS_HOST_B'),
                'password' => env('REDIS_PASSWORD_B'),
                'port'     => env('REDIS_PORT_B', 6379),
                'database' => env('REDIS_DB_B', 0),
            ],
            [
                'host'     => env('REDIS_HOST_C'),
                'password' => env('REDIS_PASSWORD_C'),
                'port'     => env('REDIS_PORT_C', 6379),
                'database' => env('REDIS_DB_C', 0),
            ],
            [
                'host'     => env('REDIS_HOST_D'),
                'password' => env('REDIS_PASSWORD_D'),
                'port'     => env('REDIS_PORT_D', 6379),
                'database' => env('REDIS_DB_D', 0),
            ],
            [
                'host'     => env('REDIS_HOST_E'),
                'password' => env('REDIS_PASSWORD_E'),
                'port'     => env('REDIS_PORT_E', 6379),
                'database' => env('REDIS_DB_E', 0),
            ],
            [
                'host'     => env('REDIS_HOST_F'),
                'password' => env('REDIS_PASSWORD_F'),
                'port'     => env('REDIS_PORT_F', 6379),
                'database' => env('REDIS_DB_F', 0),
            ],
        ],
    ],
],
# ...