RedisCluster集群方案是Redis官方推荐的一种集群方案，他没有中心节点。客户端与redis节点直连，不需要中间代理层，RedisCluster集群方案可以将数据分片存储。为避免其中一个节点宕机丢失分片数据，我们需要设置冗余节点。

• 架构设计：使用3个节点作为主节点，3个节点作为从节点（冗余节点）

  
  RedisCluster 集群方案

2.1 拉取redis 镜像

docker pull redis

3 创建私有网络

3.1 创建私有网络

创建docker容器的私有网络，方便建立集群使用，网段为172.15.0.0网络名字命名为redis_net1.(ps: 如果提醒网段被占用，请自行改为其他网段，如: 172.16.0.01 172.17.0.0 ...)

docker network create --subnet=172.15.0.0/16 redis_net1

3.2 查看网络

docker network inspect redis_net1

4 在宿主机中创建目录

4.1 创建目录 /bizwork/redis-cluster

之后会在 /bizwork/redis-cluster目录下存放配置文件以及数据

mkdir -p /bizwork/redis-cluster

4.2 准备好配置文件

在/bizwork/redis-cluster目录下 创建文件redis-cluster.tmpl

vim /bizwork/redis-cluster/redis-cluster.tmpl

将以下内容拷贝到redis-cluster.tmpl 文件中，我们后续会用到

port ${PORT}
requirepass 1234
masterauth 1234
protected-mode no
daemonize no
appendonly yes
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 15000
cluster-announce-ip xx.xx.xx.xx #你的公网IP或者内网IP
cluster-announce-port ${PORT}
cluster-announce-bus-port 1${PORT}
bind 0.0.0.0

在宿主机/bizwork/redis-cluster批量创建 8000~8005 目录,用来作为容器映射目录

for port in `seq 8000 8005`; do \
    mkdir -p ./${port}/conf \
    && PORT=${port} envsubst < ./redis-cluster.tmpl > ./${port}/conf/redis.conf \
    && mkdir -p ./${port}/data; \
done

批量创建容器

for port in `seq 8000 8005`; do \
    docker run -d -ti -p ${port}:${port} -p 1${port}:1${port}  \
    -v /bizwork/redis-cluster/${port}/conf/redis.conf:/usr/local/etc/redis/redis.conf \
    -v /bizwork/redis-cluster/${port}/data:/data \
    --restart always --name redis-${port} --net redis_net1 \
    --sysctl net.core.somaxconn=1024 redis \
    redis-server /usr/local/etc/redis/redis.conf; 
done

查看各容器的网段

docker network inspect redis_net1 

输出结果：

[
    {
        "Name": "redis_net1",
        "Id": "01cf151982fdcfa6d59a1c0cf1f82e8778ea5caf55e4ef1101501485b402a5f2",
        "Created": "2020-12-31T15:17:28.223939985+08:00",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": {},
            "Config": [
                {
                    "Subnet": "172.15.0.0/16"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {
            "2c908a8d54f9701858f774f0532304687b88b8327cac2e6b607cdf56652e3e58": {
                "Name": "redis-8002",
                "EndpointID": "c3866ce9080d1c446c2861280a15b89e53fef524dcba05623bdf9bc5cec74355",
                "MacAddress": "02:42:ac:0f:00:04",
                "IPv4Address": "172.15.0.4/16",
                "IPv6Address": ""
            },
            "9e73858fd0c192d5be38a5ee9a79650f109f3b669bbcb0e8fb7f3f5105931f85": {
                "Name": "redis-8001",
                "EndpointID": "ef52a366f26a45a06e2da4b4201955308df7379631c9d5dff35691df1cb66fe0",
                "MacAddress": "02:42:ac:0f:00:03",
                "IPv4Address": "172.15.0.3/16",
                "IPv6Address": ""
            },
            "aef661f9c8e16b490624b1fd4ed7883659addf7b1aacb13ef9c3b4737bb44a5c": {
                "Name": "redis-8005",
                "EndpointID": "c6e74a5a3de2da545d826097c44c686821c65f01164d35986629b9a1d0838cec",
                "MacAddress": "02:42:ac:0f:00:07",
                "IPv4Address": "172.15.0.7/16",
                "IPv6Address": ""
            },
            "c5320fc978908440ab52f05f821162c38baaebde4a72abce5e66d9827f7fc010": {
                "Name": "redis-8000",
                "EndpointID": "9b73ee6eb6dbd63722b0275471fde1cae2bd5907c60179fcbc25522ba0e84eb5",
                "MacAddress": "02:42:ac:0f:00:02",
                "IPv4Address": "172.15.0.2/16",
                "IPv6Address": ""
            },
            "c8ad19e2bd4bfe21968b0105d972ab0140707383a8e33a554c5b205df28953bd": {
                "Name": "redis-8003",
                "EndpointID": "4f84d1ff1cef06b267d97fd1904e11836333a7e6e51c687d849b8767dd1be7fe",
                "MacAddress": "02:42:ac:0f:00:05",
                "IPv4Address": "172.15.0.5/16",
                "IPv6Address": ""
            },
            "e002e46453501bdf3d7e9cd7d214db63fa981ab053cd5e5bdd10b9fb566839ac": {
                "Name": "redis-8004",
                "EndpointID": "cb36c1d2d8902e9d1c04599e86caf51a4d705960be7ac6e8a7b4b26a1175fbe5",
                "MacAddress": "02:42:ac:0f:00:06",
                "IPv4Address": "172.15.0.6/16",
                "IPv6Address": ""
            }
        },
        "Options": {},
        "Labels": {}
    }
]

这里我们可看出：

• 容器 redis-8000 网段为 172.15.0.2
• 容器 redis-8001 网段为 172.15.0.3
• 容器 redis-8002 网段为 172.15.0.4
• 容器 redis-8003 网段为 172.15.0.5
• 容器 redis-8004 网段为 172.15.0.6
• 容器 redis-8005 网段为 172.15.0.7

5. 创建集群

任意进入一个容器，我这里进入redis-8000容器来执行命令创建集群

docker exec -it redis-8000 bash

使用redis-cli --cluster create命令创建集群(如果设置了密码，需要输入密码参数)具体如下：

redis-cli -a 1234 --cluster create 172.15.0.2:8000 172.15.0.3:8001 172.15.0.4:8002 172.15.0.5:8003 172.15.0.6:8004 172.15.0.7:8005 --cluster-replicas 1

常见问题：

基于自己搭建redis cluster踩过的坑，希望能节约大家时间。

1、访问出现 Redis： ERR unknown command 'CLUSTER'

项目配置好集群后，访问报错ERR unknown command 'CLUSTER',原因是redis cluster服集群没有搭建成功，我再次检查了一下，未搭建成功的原因是我的redis-8000容器的配置文件的cluster-config-file node_8000.conf 与其他容器中的cluster-config-file node_8000.conf相同

2、Redis无法使用其他库

Redis Cluster 集群方案只支持一个数据库（db 0）

3、SpringBoot 配置集群无法启动

2021-01-02 21:33:39.990 ERROR 10096 --- [isson-netty-2-7] o.r.cluster.ClusterConnectionManager     : Can't connect to master: redis://172.21.0.12:8000 with slot ranges: [[0-5460]]
2021-01-02 21:33:39.991 ERROR 10096 --- [isson-netty-2-8] o.r.cluster.ClusterConnectionManager     : Can't connect to master: redis://172.21.0.12:8002 with slot ranges: [[10923-16383]]
2021-01-02 21:33:39.990 ERROR 10096 --- [isson-netty-2-9] o.r.cluster.ClusterConnectionManager     : Can't connect to master: redis://172.21.0.12:8001 with slot ranges: [[5461-10922]]