192.168.150.15 elk-node01
192.168.150.16 elk-node02
192.168.150.17 elk-node03

安装redis服务

以下操作分别在node01、node02上安装redis服务：

#yum install redis -y
安装不上的请先配置epel扩展源。

修改主从配置：

# vim /etc/redis.conf
更改如下：
bind 0.0.0.0  //或者直接写自己的IP地址
daemonize yes  //守护进程的方式
appendonly yes  //持久化保存

 重启并设置开机自启动：# systemctl restart redis
                                        # systemctl enable redis

从redis比主配置多一行：
slaveof 192.168.150.15 6379

 Keepalived安装 -----node01 node02 两个节点都安装

# yum install -y keepalived

 redis+keepalived配置

1>、node01主节点配置

#vim /etc/keepalived/keepalived.conf
里面配置如下：
global_defs {
router_id redis-master
}
vrrp_script chk_redis {
script "killall -0 redis-server"
interval 2
timeout 2
fall 3
}
vrrp_instance redis {
state BACKUP
interface ens33
lvs_sync_daemon_interface ens33
virtual_router_id 202
priority 150
nopreempt
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.150.100
}
track_script {
chk_redis
}
notify_master "/etc/keepalived/scripts/redis_master.sh 127.0.0.1 192.168.150.16
6379"
notify_backup "/etc/keepalived/scripts/redis_backup.sh 127.0.0.1 192.168.150.16
6379"
notify_fault /etc/keepalived/scripts/redis_fault.sh
notify_stop /etc/keepalived/scripts/redis_stop.sh
}

node01主节点:
#cd /etckeepalived/
#mkdir scripts
#cd scripts

脚本1：
#vim redis_master.sh
#!/bin/bash
REDISCLI="redis-cli -h $1 -p $3"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[master]" >> $LOGFILE
date >> $LOGFILE
echo "Being master...." >> $LOGFILE 2>&1
echo "Run SLAVEOF cmd ... " >> $LOGFILE
$REDISCLI SLAVEOF $2 $3 >> $LOGFILE 2>&1
echo "SLAVEOF $2 cmd can't excute ... " >> $LOGFILE
sleep 10
echo "Run SLAVEOF NO ONE cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1
：wq

脚本2 ：
#vim redis_backup.sh
#!/bin/bash
REDISCLI="redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[BACKUP]" >> $LOGFILE
date >> $LOGFILE
echo "Being slave...." >> $LOGFILE 2>&1
echo "Run SLAVEOF cmd ..." >> $LOGFILE 2>&1
$REDISCLI SLAVEOF $2 $3 >> $LOGFILE
sleep 100
exit 0
：wq

脚本3：
#vim redis_fault.sh
#!/bin/bash
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[fault]" >> $LOGFILE
date >> $LOGFILE
:wq

脚本4：
#vim redis_stop.sh
#!/bin/bash
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[stop]" >> $LOGFILE
date >> $LOGFILE
:wq

给权限：
#chmod +x *.sh

2> node02从节点配置：

 将主节点配置文件拷贝至从节点配置中：

#scp /etc/keepalived/keepalived.conf elk-node02:/etc/keepalived/

 将主节点脚本文件拷贝至从节点中：

#scp -r /etc/keepalived/scripts/  elk-node02:/etc/keepalived/

 在从节点上：在进行修改配置文件：

#vim /etc/keepalived/keepalived.conf

router_id redis-slave
priority 100   //优先级要低，主要决定谁是主从节点。
notify_master "/etc/keepalived/scripts/redis_master.sh 127.0.0.1 192.168.150.15
6379"
notify_backup "/etc/keepalived/scripts/redis_backup.sh 127.0.0.1 192.168.150.15
6379"
notify_fault /etc/keepalived/scripts/redis_fault.sh
notify_stop /etc/keepalived/scripts/redis_stop.sh
：wq

主从节点启动服务

# systemctl restart keepalived.service
# systemctl enable keepalived.service

redis+keepalived测试  

通过VIP连接Redis:

# redis-cli -h 192.168.150.100 INFO|grep role
role:master
# redis-cli -h 192.168.150.15 INFO|grep role
role:master
# redis-cli -h 192.168.150.16 INFO|grep role
role:slave

 插入数据测试:

# redis-cli -h 192.168.150.100 SET Hello Redis
OK
获取数值：
# redis-cli -h 192.168.150.100 GET Hello
"Redis"
# redis-cli -h 192.168.150.15 GET Hello
"Redis"
# redis-cli -h 192.168.150.16 GET Hello
"Redis"

模拟故障测试:

先停止redis服务 ：  #systemctl stop redis 
查看日志：
[root@elk-node01 ~]# tailf /var/log/keepalived-redis-state.log
[fault]
2019年 11月 26日 星期二 22:54:07 CST
# redis-cli -h 192.168.150.100 INFO|grep role
role:master
# redis-cli -h 192.168.150.15 INFO|grep role
Could not connect to Redis at 192.168.150.11:6379: Connection refused
# redis-cli -h 192.168.150.16 INFO|grep role
role:master

 

继续查看如下：
# redis-cli -h 192.168.150.100 INFO|grep role   //任何时候查看都是master
role:master
# redis-cli -h 192.168.150.15 INFO|grep role 
Could not connect to Redis at 192.168.150.11:6379: Connection refused
# redis-cli -h 192.168.150.16 INFO|grep role
role:master 

 恢复主节点redis:

[root@elk-node01 ~]# systemctl start redis

监控主日志，发现进入Fault状态呼notify_fault：

从节点在连接：

 [root@elk-node01 ~]# tailf /var/log/keepalived-redis-state.log
[BACKUP]
2019年 11月 26日 星期二 22:57:42 CST
Being slave....
Run SLAVEOF cmd ...
OK
# redis-cli -h 192.168.150.100 INFO|grep role
role:master
# redis-cli -h 192.168.150.15 INFO|grep role
role:slave

  再停止从节点redis服务：

# systemctl stop redis

 监控日志，发现进入Fault状态呼叫notify_fault。