redis通过哨兵模式实现主从切换

环境：

• server1：172.25.70.1 master
• server2：172.25.70.2 slave
• server3：172.25.70.3 slave

一、配置一主多从环境

1.解压

[root@server1 ~]# tar zxf redis-5.0.3.tar.gz
[root@server1 ~]# ls
redis-5.0.3 redis-5.0.3.tar.gz
[root@server1 ~]#


2.下载安装编译所需gcc

yum install -y gcc


3.make && make install

[root@server1 ~]# cd redis-5.0.3/
[root@server1 redis-5.0.3]# ls
00-RELEASENOTES INSTALL runtest tests
BUGS Makefile runtest-cluster utils
CONTRIBUTING MANIFESTO runtest-sentinel
COPYING README.md sentinel.conf
deps redis.conf src
[root@server1 redis-5.0.3]# make
[root@server1 ~]# cd src/
[root@server1 src]# make install


4.安装

[root@server1 redis-5.0.3]# cd utils/
[root@server1 utils]# ./install_server.sh
Welcome to the redis service installer
This script will help you easily set up a running redis server
Please select the redis port for this instance: [6379]
Selecting default: 6379
Please select the redis config file name [/etc/redis/6379.conf]
Selected default - /etc/redis/6379.conf
Please select the redis log file name [/var/log/redis_6379.log]
Selected default - /var/log/redis_6379.log
Please select the data directory for this instance [/var/lib/redis/6379]
Selected default - /var/lib/redis/6379
Please select the redis executable path [/usr/local/bin/redis-server]
Selected config:
Port : 6379
Config file : /etc/redis/6379.conf
Log file : /var/log/redis_6379.log
Data dir : /var/lib/redis/6379
Executable : /usr/local/bin/redis-server
Cli Executable : /usr/local/bin/redis-cli
Is this ok? Then press ENTER to go on or Ctrl-C to abort.
Copied /tmp/6379.conf => /etc/init.d/redis_6379
Installing service...
Successfully added to chkconfig!
Successfully added to runlevels 345!
Starting Redis server...
Installation successful!


5.修改配置文件，并重启服务

[root@server1 utils]# vim /etc/redis/6379.conf
=====================
70 bind 0.0.0.0
========================
[root@server1 utils]# /etc/init.d/redis_6379 restart
Stopping ...
Redis stopped
Starting Redis server...


#查看端口

[root@server1 utils]# netstat -antlupe | grep 6379
tcp 0 0 0.0.0.0:6379 0.0.0.0:* LISTEN 0 100152 7413/redis-server 0


6.将make完的redis发送给server2、server3

[root@server1 ~]# scp -r redis-5.0.3 root@server2:
[root@server1 ~]# scp -r redis-5.0.3 root@server3:


7.安装配置server2、server3

[root@server2 redis-5.0.3]# cd src/
[root@server2 src]# make install
[root@server2 src]# cd ../utils/
[root@server2 utils]# ./install_server.sh
[root@server2 utils]# vim /etc/redis/6379.conf
===============================================
70 bind 0.0.0.0
1379 slaveof 172.25.70.1 6379
=================================================
[root@server2 utils]# /etc/init.d/redis_6379 restart


#在server1上查看主从状态

[root@server1 redis-5.0.3]# redis-cli
127.0.0.1:6379> info
'''
# Replication
role:master
connected_slaves:2
slave0:ip=172.25.70.2,port=6379,state=online,offset=630,lag=1
slave1:ip=172.25.70.3,port=6379,state=online,offset=630,lag=1


server3操作同server2


server1上再次查看主从

• server2
  
• server3
  

二、哨兵机制

1.复制哨兵配置文件到redis配置文件目录

[root@server1 ~]# cd redis-5.0.3/
[root@server1 redis-5.0.3]# cp sentinel.conf /etc/redis/


2.修改哨兵配置文件

vim /etc/redis/sentinel.conf
====================================================
84 sentinel monitor mymaster 172.25.70.1 6379 2
...
113 sentinel down-after-milliseconds mymaster 10000


3.给server2、server3发送哨兵文件

[root@server1 redis-5.0.3]# cd /etc/redis/
[root@server1 redis]# scp sentinel.conf server2:/etc/redis/
sentinel.conf 100% 9712 9.5KB/s 00:00
[root@server1 redis]# scp sentinel.conf server3:/etc/redis/
sentinel.conf 100% 9712 9.5KB/s 00:00
[root@server1 redis]#


4.server1-3执行哨兵

• server1：

[root@server1 redis]# redis-server /etc/redis/sentinel.conf --sentinel


• server2：

[root@server2 utils]# redis-server /etc/redis/sentinel.conf --sentinel


• server3:

[root@server3 utils]# redis-server /etc/redis/sentinel.conf --sentinel


可以看到信息，server1为master，server2-3都是slave节点。

5.测试

1.重新开启一个终端远程连接server1查看端口发现哨兵26379进程开启：

[root@server1 ~]# netstat -antulpe


2.查看26479端口

[root@server1 ~]# redis-cli -p 26379


注意：此时显示主是server1，sentinels=3表示成功
3.将server1的redis-cli关闭

[root@server1 ~]# redis-cli
127.0.0.1:6379> SHUTDOWN
not connected>


4.查看哨兵状态

我们可以看到此时哨兵为我们挑选了server3作为新的master

5.连接server2，查看redis状态

server3成为master

我们在新的master上写入信息，再在server2上查看：

• server2
  
  哨兵模式配置完毕