Docker中redis集群部署实战

2022-11-27 12:00

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环境准备

Redis是C语言开发，安装Redis需要先将Redis的源码进行编译，编译依赖gcc环境

安装`gcc-c++`

yum install gcc-c++

查看版本

[root@--- redis]# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-RedHat-linux/4.8.5/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,Java,fortran,ada,go,lto --enable-plugin --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/cloog-install --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC) 
[root@--- redis]#

Redis的四种模式

单机模式
master+slave(主从)
sentinel(哨兵)
cluster(集群)

创建redis网卡

[root@--- ~]# docker network create redis --subnet 172.38.0.0/16
0350d84612bef09bc32b39f15ac6b608dae17cbd75d04b282c0bd37c0283bb7c
[root@iZm5e23n3ueobwkjtfartxZ ~]# docker network ls
NETWORK ID     NAME           DRIVER    SCOPE
feafa30d4051   bridge         bridge    local
e8bf4fced9e2   host           host      local
0096a971fd2c   mynet          bridge    local
6263db0933b9   none           null      local
0350d84612be   redis          bridge    local
799426d70aa2   test-network   bridge    local
[root@--- ~]#

创建6个redis服务

通过编写脚本创建6个redis服务

cluster-enabled：是否启动集群，选值：yes 、no
cluster-config-file 配置文件.conf ：指定节点信息，自动生成
cluster-node-timeout 毫秒值：配置节点连接超时时间
appendonly：是否开启持久化，选值：yes、no
daemonize: 守护进程启动(后台启动)

在`/var`目录下创建脚本文件`create_redis_script.sh`

touch create_redis_script.sh

编写脚本内容

vim create_redis_script.sh，写入下面的内容

for port in $(seq	1 6); \
do \
mkdir -p /var/redisNode/node-${port}/conf
touch /var/redisNode/node-${port}/conf/redis.conf
cat << EOF >/var/redisNode/node-${port}/conf/redis.conf
port 6379
bind 0.0.0.0
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
cluster-announce-ip 172.38.0.1${port}
cluster-announce-port 6379
cluster-announce-bus-port 16379
appendonly yes
#daemonize yes
EOF
done

查看脚本文件

cat create_redis_script.sh

赋予`create_redis_script.sh`文件可执行权限

[root@--- ~]# chmod o+x create_redis_script.sh

执行脚本，创建redis服务

./create_redis_script.sh

查看redis节点

[root@--- redisNode]# pwd
/var/redisNode
[root@--- redisNode]# ls
node-1  node-2  node-3  node-4  node-5  node-6
[root@--- redisNode]#

查看redis.conf配置文件

Docker中redis集群部署实战

启动redis服务

-v 挂载数据卷
redis:5.0.9-alpine3.11 redis镜像
6379 是redis端口：映射云服务器端口6371 - 6376
16379 是redis集群TCP端口：映射云服务器端口16371 - 16376
--net 使用自定义redis网络
--ip 是本容器绑定的ip： 172.38.0.11 - 16
--name 容器名字： redis-1 - 6
redis-server /etc/redis/redis.conf 追加命令，通过redis.conf启动

启动方式一（不推荐）：

一个一个启动

启动第一个redis节点

docker run -p 6371:6379 -p 16371:16379 --name redis-1 \
-v /var/redisNode/node-1/data:/data \
-v /var/redisNode/node-1/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.11 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

如上，类似的，递增ip、port和name，启动其它五个redis节点，太麻烦了，可以通过编写脚本来一次启动6个服务

启动方式二（推荐）：

编写启动脚本，6个全部启动

创建`start_redis_script.sh`文件

touch start_redis_script.sh

编写脚本内容

vim start_redis_script.sh，写入下面的内容

for port in $(seq	1 6); \
do \
echo ${port}
docker run -p 637${port}:6379 -p 1637${port}:16379 --name redis-${port} \
-v /var/redisNode/node-${port}/data:/data \
-v /var/redisNode/node-${port}/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.1${port} redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf; \
done

赋予`start_redis_script.sh`文件可执行权限

[root@--- ~]# chmod o+x start_redis_script.sh

执行脚本，启动redis容器服务

./start_redis_script.sh

Docker中redis集群部署实战

查看redis容器

[root@--- var]# docker ps
CONTAINER ID   IMAGE                    COMMAND                  CREATED              STATUS              PORTS                                              NAMES
0d3c18b61098   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   2 seconds ago        Up 1 second         0.0.0.0:6376-&gt;6379/tcp, 0.0.0.0:16376-&gt;16379/tcp   redis-6
ee896fb093da   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   13 seconds ago       Up 12 seconds       0.0.0.0:6375-&gt;6379/tcp, 0.0.0.0:16375-&gt;16379/tcp   redis-5
a83bb7b16dff   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   48 seconds ago       Up 47 seconds       0.0.0.0:6374-&gt;6379/tcp, 0.0.0.0:16374-&gt;16379/tcp   redis-4
ffe4c9619bed   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   58 seconds ago       Up 57 seconds       0.0.0.0:6373-&gt;6379/tcp, 0.0.0.0:16373-&gt;16379/tcp   redis-3
a316a31e273f   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   About a minute ago   Up About a minute   0.0.0.0:6372-&gt;6379/tcp, 0.0.0.0:16372-&gt;16379/tcp   redis-2
71c072f57c29   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   9 minutes ago        Up 9 minutes        0.0.0.0:6371-&gt;6379/tcp, 0.0.0.0:16371-&gt;16379/tcp   redis-1
[root@--- var]#

创建集群

进入任意一个 Redis 实例

进入redis-1容器

docker exec -it redis-1 /bin/sh

创建集群主节点

Redis Cluster最低要求是3个主节点
--cluster-replicas 参数为数字，1表示每个主节点需要1个从节点。

# redis-1 容器内
/data # redis-cli --cluster create 172.38.0.11:6379 172.38.0.12:6379 172.38.0.13:6379 172.38.0.14:6379 172.38.0.15:6379 172.38.0.16:6379 --cluster-replicas 1

Docker中redis集群部署实战

测试连接集群

连接集群 `-c`

# redis-1 容器内
/data # redis-cli -c
127.0.0.1:6379>

查看集群信息 `cluster info`

127.0.0.1:6379> cluster info
cluster_state:ok
cluster_slots_assigned:16384
cluster_slots_ok:16384
cluster_slots_pfail:0
cluster_slots_fail:0
cluster_known_nodes:6
cluster_size:3
cluster_current_epoch:6
cluster_my_epoch:1
cluster_stats_messages_ping_sent:292
cluster_stats_messages_pong_sent:307
cluster_stats_messages_sent:599
cluster_stats_messages_ping_received:302
cluster_stats_messages_pong_received:292
cluster_stats_messages_meet_received:5
cluster_stats_messages_received:599
127.0.0.1:6379>

查看节点信息 `cluster nodes`

127.0.0.1:6379> cluster nodes
b3f737d0d77b823794087011f1501fd43a2ea316 172.38.0.12:6379@16379 master - 0 1633332452560 2 connected 5461-10922
506ff2bf1020d468e7d7a81ddbfb616a7e9b7d96 172.38.0.13:6379@16379 master - 0 1633332453000 3 connected 10923-16383
7f57f8a01493fa9e46e24ad8a9e46995634f7442 172.38.0.15:6379@16379 slave 70ebdca0264c079bb2c33452e6388d37706da282 0 1633332453000 5 connected
70ebdca0264c079bb2c33452e6388d37706da282 172.38.0.11:6379@16379 myself,master - 0 1633332452000 1 connected 0-5460
f839b6924977e99d3b74324f2ef70b3678e1a257 172.38.0.14:6379@16379 slave 506ff2bf1020d468e7d7a81ddbfb616a7e9b7d96 0 1633332453762 4 connected
bbc4dd0639b90e9ddfb5cef278be04a24276cbdb 172.38.0.16:6379@16379 slave b3f737d0d77b823794087011f1501fd43a2ea316 0 1633332453000 6 connected
127.0.0.1:6379>

Docker中redis集群部署实战

测试主从节点替换

验证高可用

set一个值，然后停掉对应的服务，再次get，验证是否可以得到值

set值

127.0.0.1:6379&gt; set a b
-&gt; Redirected to slot [15495] located at 172.38.0.13:6379
OK
172.38.0.13:6379&gt;

发现a值设置在了172.38.0.13容器上，然后我们试着去停掉redis-3容器的服务，然后再次get,看一下结果

get值

172.38.0.13:6379&gt; get a
"b"
172.38.0.13:6379&gt;

停止`redis-3`容器里的redis服务

docker stop redis-3

再次取值

172.38.0.13:6379&gt; get a
Could not connect to Redis at 172.38.0.13:6379: Host is unreachable
(34.04s)
not connected&gt; exit
# 重连集群
/data # redis-cli -c
127.0.0.1:6379&gt; get a
-&gt; Redirected to slot [15495] located at 172.38.0.14:6379
"b"
172.38.0.14:6379&gt;

发现a值被存储到了172.38.0.14机器上，172.38.0.14是172.38.0.13的从节点，当主节点172.38.0.13发生故障时，自动替换到172.38.0.13，这就是高可用