redis(三)redis+Keepalived主從熱備秒級切換
一 簡介
安裝使用centos 5.10
Master 192.168.235.135
Slave 192.168.235.152
Vip 192.168.235.200
編譯環境 yum -y install gcc gcc+ gcc-c++ openssl openssl-devel pcre pcre-devel
當 Master 與 Slave 均運作正常時, Master負責服務，Slave負責Standby；
當 Master 掛掉，Slave 正常時, Slave接管服務，同時關閉主從複製功能；
當 Master 恢復正常，則從Slave同步資料，同步資料之後關閉主從複製功能，恢復Master身份，於此同時Slave等待Master同步資料完成之後，恢復Slave身份。
然後依次迴圈。
需要注意的是，這樣做需要在Master與Slave上都開啟本地化策略，否則在互相自動切換的過程中，未開啟本地化的一方會將另一方的資料清空，造成資料完全丟失
二 安裝
tar xf keepalived-1.2.12.tar.gz
cd keepalived-1.2.12
./configure
make && make install
cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/
cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
chmod +x /etc/init.d/keepalived
chkconfig –add keepalived
mkdir /etc/keepalived
ln –s /usr/local/sbin/keepalived /usr/sbin
三 配置
首先在master上建立如下配置
mkdir –p /etc/keepalived
vim /etc/keepalived/keepalived.conf
//加入如下內容指令碼
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh" ###監控指令碼
interval 2 ###監控時間
}
vrrp_instance VI_1 {
state MASTER ###設定為MASTER
interface eth0 ###監控網絡卡
virtual_router_id 51
priority 101 ###權重值
authentication {
auth_type PASS ###加密
auth_pass redis ###密碼
}
track_script {
chk_redis ###執行上面定義的chk_redis
}
virtual_ipaddress {
192.168.235.200 ###VIP
}
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
}
vim /etc/keepalived/scripts/redis_master.sh
#!/bin/bash
REDISCLI="/opt/redis/bin/redis-cli"
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 192.168.135.152(slave) 6379 >> $LOGFILE 2>&1
sleep 10 #延遲10秒以後待資料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
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[backup]" >> $LOGFILE
date >> $LOGFILE
echo "Being slave...." >> $LOGFILE 2>&1
sleep 15 #延遲15秒待資料被對方同步完成之後再切換主從角色
echo "Run SLAVEOF cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF 192.168.135.152(slave) 6379 >> $LOGFILE 2>&1
在slave上建立如下檔案：
vim /etc/keepalived/keepalived.conf
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh" ###監控指令碼
interval 2 ###監控時間
}
vrrp_instance VI_1 {
state BACKUP ###設定為BACKUP
interface eth0 ###監控網絡卡
virtual_router_id 51
priority 100 ###比MASTRE權重值低
authentication {
auth_type PASS
auth_pass redis ###密碼與MASTRE相同
}
track_script {
chk_redis ###執行上面定義的chk_redis
}
virtual_ipaddress {
192.168.235.200 ###VIP
}
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
}
vim /etc/keepalived/scripts/redis_master.sh
#!/bin/bash
REDISCLI="/opt/redis/bin/redis-cli"
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 192.168.235.135(master) 6379 >> $LOGFILE 2>&1
sleep 10 #延遲10秒以後待資料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
REDISCLI="/opt/redis/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[backup]" >> $LOGFILE
date >> $LOGFILE
echo "Being slave...." >> $LOGFILE 2>&1
sleep 15 #延遲15秒待資料被對方同步完成之後再切換主從角色
echo "Run SLAVEOF cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF 10.6.1.143 6379 >> $LOGFILE 2>&1
以下指令碼分別在master和slave上建立
mkdir /etc/keepalived/scripts
vim /etc/keepalived/scripts/redis_check.sh
#!/bin/bash
ALIVE=`/opt/redis/bin/redis-cli PING`
if [ "$ALIVE" == "PONG" ]; then
echo $ALIVE
exit 0
else
echo $ALIVE
exit 1
fi
vim /etc/keepalived/scripts/redis_fault.sh
#!/bin/bash
LOGFILE=/var/log/keepalived-redis-state.log
echo "[fault]" >> $LOGFILE
date >> $LOGFILE
vim /etc/keepalived/scripts/redis_stop.sh
#!/bin/bash
LOGFILE=/var/log/keepalived-redis-state.log
echo "[stop]" >> $LOGFILE
date >> $LOGFILE
授執行權 chmod +x /etc/keepalived/scripts/*.sh
測試
在msater和slave上分別啟動redis；
Service redis start
分別啟動keepalived
Service keepalived start
在master上執行 ip a
虛擬IP已經綁定了
在master上執行service redis stop 檢視slave
看到了吧秒級切換。
接下來再吧master上的redis啟動起來
又切換回來了。
測試redis同步
到此安裝完成了。