CentOS下Redis高可用安裝筆記

(WJW)Redis高可用安裝筆記

[x] 安裝環境介紹:

Master: T1
Slave: T2
VIP: 192.168.68.45

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[x] 安裝Redis(Master,Slave)

注意: 安裝redis前flushall的修改

查找src/redis.c文件,把
{"flushdb",flushdbCommand,1,"w",0,NULL,0,0,0,0,0},
{"flushall",flushallCommand,1,"w",0,NULL,0,0,0,0,0},
修改爲:
{"xflushdb",flushdbCommand,1,"w",0,NULL,0,0,0,0,0},
{"xflushall",flushallCommand,1,"w",0,NULL,0,0,0,0,0},

vi /etc/sysctl.conf
添加一行: `vm.overcommit_memory=1`

mkdir /opt/redis
mkdir /opt/redis/log
mkdir /opt/redis/db

tar zxvf ./redis-2.8.17.tar.gz
cd redis-2.8.17
make PREFIX=/opt/redis install

[x] Redis啓動腳本(Master,Slave):/opt/redis/bin/startRedis.sh

#!/bin/bash

basedir=`dirname $0`
echo "Redis BASE DIR:$basedir"
cd $basedir

nohup ./redis-server ./redis.conf > /dev/null 2>&1 &

[x] Redis中止腳本(Master,Slave):/opt/redis/bin/StopRedis.sh

#!/bin/sh

basedir=`dirname $0`
echo "Redis BASE DIR:$basedir"
cd $basedir

./redis-cli -h localhost -a 123456 shutdown

[x] Redis配置文件(Master,Slave):/opt/redis/bin/redis.conf

#requirepass 123456

pidfile /opt/redis/bin/redis.pid
logfile /opt/redis/log/redis.log
dir /opt/redis/db/

daemonize yes
port 6379
timeout 300
loglevel warning
databases 16
maxmemory 1g

#不要快照
#save 900 1
#save 300 10
#save 60 10000
#rdbcompression yes
#dbfilename dump.rdb

#使用AOF
appendonly yes
appendfsync everysec

[x] 安裝Keepalived(Master,Slave):

#wget http://www.keepalived.org/software/keepalived-1.2.13.tar.gz
tar zxvf keepalived-1.2.13.tar.gz
cd ./keepalived-1.2.13
./configure
make 
make install

cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
cp /usr/local/sbin/keepalived /usr/sbin/
mkdir /etc/keepalived
cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/
chkconfig --add keepalived
#chkconfig --level 35 keepalived on
#service keepalived start

[x] notify_*解釋

Keepalived在轉換狀態時會依照狀態來呼叫：
當進入Master狀態時會呼叫notify_master
當進入Backup狀態時會呼叫notify_backup
當發現異常狀況時(track_script,track_interface失敗)進入Fault狀態呼叫notify_fault
當Keepalived程序終止時則呼叫notify_stop

[x] 在Master上建立以下配置文件：

vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   notification_email {
     root@localhost
   }
   notification_email_from root@localhost
   smtp_server localhost
   smtp_connect_timeout 30
   router_id LVS_REDIS
}

vrrp_script chk_redis {
  script "/etc/keepalived/scripts/redis_check.sh"   ###監控腳本
  interval 2                                        ###監控時間
}

vrrp_instance VI_1 {
    nopreempt ###不搶佔,防止腦裂
    state MASTER             #備的是BACKUP
    interface br0
    virtual_router_id 51
    priority 100            #備的是90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass redis
    }
    virtual_ipaddress {
        192.168.68.45
    }
    
    track_script {
      chk_redis                       ###執行上面定義的chk_redis
    }
    
    notify_master /etc/keepalived/scripts/redis_master.sh
    notify_backup /etc/keepalived/scripts/redis_backup.sh
    notify_fault  /etc/keepalived/scripts/redis_fault.sh
    notify_stop   /etc/keepalived/scripts/redis_stop.sh
}

[x] 在Slave上建立以下配置文件：

vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   notification_email {
     root@localhost
   }
   notification_email_from root@localhost
   smtp_server localhost
   smtp_connect_timeout 30
   router_id LVS_REDIS
}

vrrp_script chk_redis {
  script "/etc/keepalived/scripts/redis_check.sh"   ###監控腳本
  interval 2                                        ###監控時間
}

vrrp_instance VI_1 {
    nopreempt ###不搶佔,防止腦裂
    state BACKUP             #備的是BACKUP
    interface br0
    virtual_router_id 51
    priority 90            #備的是90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass redis
    }
    virtual_ipaddress {
        192.168.68.45
    }
    
    track_script {
      chk_redis                       ###執行上面定義的chk_redis
    }
    
    notify_master /etc/keepalived/scripts/redis_master.sh
    notify_backup /etc/keepalived/scripts/redis_backup.sh
    notify_fault  /etc/keepalived/scripts/redis_fault.sh
    notify_stop   /etc/keepalived/scripts/redis_stop.sh
}

[x] 在Master和Slave上建立監控Redis的腳本:

mkdir /etc/keepalived/scripts/ vi /etc/keepalived/scripts/redis_check.sh

#!/bin/bash

C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
ALIVE=`/opt/redis/bin/redis-cli PING`

if [ "$ALIVE" == "PONG" ]; then
  echo "${C_DATE} $ALIVE"
  exit 0
else
  echo "${C_DATE} $ALIVE"
  exit 1
fi

[x] 在Master與Slave建立以下腳本notify_fault和notify_stop：

vim /etc/keepalived/scripts/redis_fault.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
LOGFILE=/var/log/keepalived-redis-state.log
 
echo "${C_DATE} [fault]" >> $LOGFILE

vim /etc/keepalived/scripts/redis_stop.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
LOGFILE=/var/log/keepalived-redis-state.log
 
echo "${C_DATE} [stop]" >> $LOGFILE

[x] 在Master上建立notity_master與notify_backup腳本:

vim /etc/keepalived/scripts/redis_master.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
 
echo "${C_DATE} [master]" >> $LOGFILE

#當keepalived配置爲"搶佔式"時,打開下面註釋
#echo "Being master...." >> $LOGFILE 2>&1
#echo "Run SLAVEOF cmd ..." >> $LOGFILE
#$REDISCLI SLAVEOF T2 6379 >> $LOGFILE  2>&1
#sleep 10 #延遲10秒之後待數據同步完成後再取消同步狀態
 
echo "Run SLAVEOF NO ONE cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1

vim /etc/keepalived/scripts/redis_backup.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
 
echo "${C_DATE} [backup]" >> $LOGFILE

#當keepalived配置爲"搶佔式"時,打開下面註釋
#echo "Being slave...." >> $LOGFILE 2>&1
#sleep 15 #延遲15秒待數據被對方同步完成以後再切換主從角色

echo "Run SLAVEOF cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF T2 6379 >> $LOGFILE  2>&1

[x] 在Slave上建立notity_master與notify_backup腳本:

vim /etc/keepalived/scripts/redis_master.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
 
echo "${C_DATE} [master]" >> $LOGFILE

#當keepalived配置爲"搶佔式"時,打開下面註釋
#echo "Being master...." >> $LOGFILE 2>&1
#echo "Run SLAVEOF cmd ..." >> $LOGFILE
#$REDISCLI SLAVEOF T1 6379 >> $LOGFILE  2>&1
#sleep 10 #延遲10秒之後待數據同步完成後再取消同步狀態
 
echo "Run SLAVEOF NO ONE cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1

vim /etc/keepalived/scripts/redis_backup.sh

#!/bin/bash
 
C_DATE=`date +"[%Y-%m-%d %H:%M:%S]"`
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
 
echo "${C_DATE} [backup]" >> $LOGFILE

#當keepalived配置爲"搶佔式"時,打開下面註釋
#echo "Being slave...." >> $LOGFILE 2>&1
#sleep 15 #延遲15秒待數據被對方同步完成以後再切換主從角色

echo "Run SLAVEOF cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF T1 6379 >> $LOGFILE  2>&1

[x] 在Master和Slave上,給監控腳本都加上可執行權限：

chmod +x /etc/keepalived/scripts/*.sh

[x] 啓動步驟:

1. 啓動Master上的Redis /opt/redis/bin/startRedis.sh

2. 啓動Slave上的Redis /opt/redis/bin/startRedis.sh

3. 啓動Master上的Keepalived service keepalived start

4. 啓動Slave上的Keepalived service keepalived start