Docker 部署redis哨兵

为什么要部署哨兵，因为我们在使用redis主从复制的时候，如果主库宕机了我们应该怎么办，这个时候我们就想到了哨兵，哨兵是redis集群架构中非常重要的一个组件，主要的功能有以下几点

1.集群监控：负责监控redis master和slave进程是否正常工作。

2.消息通知：如果某个redis实例有故障，那么哨兵负责发送消息作为报警通知给管理员。

3.故障转移：如果master node挂掉了，会自动转移到slave  node上。

4.配置中心：如果故障转移发生了，通知client客户端的master地址。

然后我们接下来开始操作。

首先我们跟前面redis主从复制一样在根目录建立配置文件的目录，建立三个分别是26379,26380,26381

[root@VM-4-6-centos redis]# ls
26379  26380  26381  6396  6397  6398
 

[root@VM-4-6-centos 26379]# pwd
/redis/26379
[root@VM-4-6-centos 26379]# 

 分别往配置文件写入相应的参数

1. port 26379

2. sentinel monitor sentinel79 服务器ip 6396 1

 

1. port 26380

2. sentinel monitor sentinel79 服务器ip 6396 1

 

1. port 26381

2. sentinel monitor sentinel79 47.94.223.116 6396 1

 --port是指定哨兵的端口

--sentinel  monitor  名称 服务器ip  要监听的端口  多少个哨兵认为宕机才会选举

创建哨兵的容器

docker run -itd -p 26398:6379 --name=sentinel98 --sysctl net.core.somaxconn=1024 -v /redis/26398/sentinel98.conf:/etc/sentinel.conf -v /root/usr/local/redis/data:/data  -e TIME_ZONE="Asia/Shanghai" -e TZ="Asia/Shanghai" -d redis 

 docker run -itd -p 26397:6379 --name=sentinel97 --sysctl net.core.somaxconn=1024 -v /redis/26397/sentinel97.conf:/etc/sentinel.conf -v /root/usr/local/redis/data:/data  -e TIME_ZONE="Asia/Shanghai" -e TZ="Asia/Shanghai" -d redis 

 docker run -itd -p 26396:6379 --name=sentinel97 --sysctl net.core.somaxconn=1024 -v /redis/26396/sentinel96.conf:/etc/sentinel.conf -v /root/usr/local/redis/data:/data  -e TIME_ZONE="Asia/Shanghai" -e TZ="Asia/Shanghai" -d redis 

 我们进入刚刚创建好的容器，开启哨兵进行监听主库，将三个哨兵依次开启，然后我们将主库的容器关闭，进行选举

[root@VM-4-6-centos 26379]# docker exec -it 9d0 bash
root@9d047c608726:/data# redis-sentinel /etc/sentinel.conf
47:X 23 Sep 2022 22:38:59.706 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
47:X 23 Sep 2022 22:38:59.706 # Redis version=7.0.4, bits=64, commit=00000000, modified=0, pid=47, just started
47:X 23 Sep 2022 22:38:59.706 # Configuration loaded
47:X 23 Sep 2022 22:38:59.706 * monotonic clock: POSIX clock_gettime
                _._                                                  
           _.-``__ ''-._                                             
      _.-``    `.  `_.  ''-._           Redis 7.0.4 (00000000/0) 64 bit
  .-`` .-```.  ```\/    _.,_ ''-._                                  
 (    '      ,       .-`  | `,    )     Running in sentinel mode
 |`-._`-...-` __...-.``-._|'` _.-'|     Port: 26381
 |    `-._   `._    /     _.-'    |     PID: 47
  `-._    `-._  `-./  _.-'    _.-'                                   
 |`-._`-._    `-.__.-'    _.-'_.-'|                                  
 |    `-._`-._        _.-'_.-'    |           https://redis.io       
  `-._    `-._`-.__.-'_.-'    _.-'                                   
 |`-._`-._    `-.__.-'    _.-'_.-'|                                  
 |    `-._`-._        _.-'_.-'    |                                  
  `-._    `-._`-.__.-'_.-'    _.-'                                   
      `-._    `-.__.-'    _.-'                                       
          `-._        _.-'                                           
              `-.__.-'                                               

47:X 23 Sep 2022 22:38:59.712 # Could not rename tmp config file (Device or resource busy)
47:X 23 Sep 2022 22:38:59.712 # WARNING: Sentinel was not able to save the new configuration on disk!!!: Device or resource busy
47:X 23 Sep 2022 22:38:59.712 # Sentinel ID is 33a9e959634aebb112e6cf991cac5e47768a2233
47:X 23 Sep 2022 22:38:59.712 # +monitor master sentinel79 121.4.33.132 6396 quorum 1
 

 [root@VM-4-6-centos 26379]# docker stop 33c
33c
[root@VM-4-6-centos 26379]# 

 当哨兵选举的时候出现以下情况证明选举成功

:X 23 Sep 2022 22:46:34.234 # Could not rename tmp config file (Device or resource busy)
36:X 23 Sep 2022 22:46:34.234 # WARNING: Sentinel was not able to save the new configuration on disk!!!: Device or resource busy
36:X 23 Sep 2022 22:47:18.476 # +sdown master sentinel79 121.4.33.132 6396
36:X 23 Sep 2022 22:47:18.476 # +odown master sentinel79 121.4.33.132 6396 #quorum 1/1
36:X 23 Sep 2022 22:47:18.476 # +new-epoch 1
36:X 23 Sep 2022 22:47:18.476 # +try-failover master sentinel79 121.4.33.132 6396
36:X 23 Sep 2022 22:47:18.484 # Could not rename tmp config file (Device or resource busy)
36:X 23 Sep 2022 22:47:18.484 # WARNING: Sentinel was not able to save the new configuration on disk!!!: Device or resource busy
36:X 23 Sep 2022 22:47:18.484 # +vote-for-leader 239b12b82a52e28965e7258d57762fbeb8b1b4e4 1
36:X 23 Sep 2022 22:47:18.484 # 95b303107a21fa578476537036131af4d837250b voted for 95b303107a21fa578476537036131af4d837250b 1
36:X 23 Sep 2022 22:47:18.491 # cdb46edf39b844d95545a3dd69c60898495863fa voted for 95b303107a21fa578476537036131af4d837250b 1
36:X 23 Sep 2022 22:47:29.091 # -failover-abort-not-elected master sentinel79 121.4.33.132 6396
36:X 23 Sep 2022 22:47:29.153 # Next failover delay: I will not start a failover before Fri Sep 23 22:53:19 2022
36:X 23 Sep 2022 22:47:55.755 * +reboot master sentinel79 121.4.33.132 6396
36:X 23 Sep 2022 22:47:55.812 # -sdown master sentinel79 121.4.33.132 6396
36:X 23 Sep 2022 22:47:55.812 # -odown master sentinel79 121.4.33.132 6396
 

 到这里我们使用Docker布置Redis主从和哨兵就布置完毕了。