Nginx+PHP+MySQL双机互备、全自动切换方案

vi /etc/rsyncd.conf

uid = root
gid = root
use chroot = no
max connections = 20
pid file = /var/run/rsyncd.pid
lock file = /var/run/rsync.lock
log file = /var/log/rsyncd.log

[data0_htdocs]
path = /data0/htdocs/
ignore errors
read only = no
hosts allow = 192.168.146.0/24
hosts deny = 0.0.0.0/32

[php_etc]
path = /usr/local/webserver/php/etc/
ignore errors
read only = no
hosts allow = 192.168.146.0/24
hosts deny = 0.0.0.0/32

[nginx_conf]
path = /usr/local/webserver/nginx/conf/
ignore errors
read only = no
hosts allow = 192.168.146.0/24
hosts deny = 0.0.0.0/32

#!/bin/sh
LANG=C
date=$(date -d "today" +"%Y-%m-%d %H:%M:%S")

#---------------配置信息(开始)---------------
#类型：主机设为master，备机设为slave
type="master"

#主机、备机切换日志路径
logfile="/var/log/failover.log"

#MySQL可执行文件地址，例如/usr/local/mysql/bin/mysql；MySQL用户名；密码；端口
mysql_bin="/usr/local/webserver/mysql/bin/mysql"
mysql_username="root"
mysql_password="123456"
mysql_port="3306"

#内网网关
gateway_eth0="192.168.146.1"

#主机内网真实IP
rip_eth0_master="192.168.146.213"

#备机内网真实IP
rip_eth0_slave="192.168.146.215"

#主机、备机内网共用的虚拟IP
vip_eth0_share="192.168.113.214"


#外网网关
gateway_eth1="72.249.146.193"

#主机外网真实IP
rip_eth1_master="72.249.146.213"

#备机外网真实IP
rip_eth1_slave="72.249.146.215"

#主机、备机外网共用的虚拟IP
vip_eth1_share="72.249.146.214"
#---------------配置信息(结束)---------------

#绑定内、外网虚拟IP
function_bind_vip()
{
/sbin/ifconfig eth0:vip ${vip_eth0_share} broadcast ${vip_eth0_share} netmask 255.255.255.255 up
/sbin/route add -host ${vip_eth0_share} dev eth0:vip
/sbin/ifconfig eth1:vip ${vip_eth1_share} broadcast ${vip_eth1_share} netmask 255.255.255.255 up
/sbin/route add -host ${vip_eth1_share} dev eth1:vip
/usr/local/webserver/php/sbin/php-fpm reload
kill -USR1 `cat /usr/local/webserver/nginx/logs/nginx.pid`
/sbin/service crond start
}

#解除内、外网虚拟IP
function_remove_vip()
{
/sbin/ifconfig eth0:vip ${vip_eth0_share} broadcast ${vip_eth0_share} netmask 255.255.255.255 down
/sbin/ifconfig eth1:vip ${vip_eth1_share} broadcast ${vip_eth1_share} netmask 255.255.255.255 down
/sbin/service crond stop
}

#主机向备机推送文件的函数
function_rsync_master_to_slave()
{
/usr/bin/rsync -zrtuog /data0/htdocs/ ${rip_eth0_slave}::data0_htdocs/ > /dev/null 2>&1
/usr/bin/rsync -zrtuog /usr/local/webserver/php/etc/ ${rip_eth0_slave}::php_etc/ > /dev/null 2>&1
/usr/bin/rsync -zrtuog /usr/local/webserver/nginx/conf/ ${rip_eth0_slave}::nginx_conf/ > /dev/null 2>&1
}

#备机向主机推送文件的函数
function_rsync_slave_to_master()
{
/usr/bin/rsync -zrtuog /data0/htdocs/ ${rip_eth0_master}::data0_htdocs/ > /dev/null 2>&1
/usr/bin/rsync -zrtuog /usr/local/webserver/php/etc/ ${rip_eth0_master}::php_etc/ > /dev/null 2>&1
/usr/bin/rsync -zrtuog /usr/local/webserver/nginx/conf/ ${rip_eth0_master}::nginx_conf/ > /dev/null 2>&1
}

#虚拟IP ARPing
function_vip_arping()
{
/sbin/arping -I eth0 -c 3 -s ${vip_eth0_share} ${gateway_eth0} > /dev/null 2>&1
/sbin/arping -I eth1 -c 3 -s ${vip_eth1_share} ${gateway_eth1} > /dev/null 2>&1
}

while true
do
#用HTTP协议检查虚拟IP
if (curl -m 30 -G http://${vip_eth1_share}/ > /dev/null 2>&1) && (${mysql_bin} -u"${mysql_username}" -p"${mysql_password}" -P"${mysql_port}" -h"${vip_eth0_share}" -e"show slave status\G" > /dev/null 2>&1)
then
#取得与内网VIP绑定的服务器内网IP
eth0_active_server=$(${mysql_bin} -u"${mysql_username}" -p"${mysql_password}" -P"${mysql_port}" -h"${vip_eth0_share}" -e"show slave status\G" | grep "Master_Host" | awk -F ': ' '{printf $2}')

#如果内网VIP=主机内网IP（主机MySQL中的Master_Host显示的是备机的域名或IP），且本机为主机
if [ "${eth0_active_server}" = "${rip_eth0_slave}" ] && [ "${type}" = "master" ]
then
function_rsync_master_to_slave
function_vip_arping
#如果内网VIP=备机内网IP（备机MySQL中的Master_Host显示的是主机的域名或IP）
elif [ "${eth0_active_server}" = "${rip_eth0_master}" ]
then
if (curl -m 30 -G http://${rip_eth1_master}/ > /dev/null 2>&1) && (${mysql_bin} -u"${mysql_username}" -p"${mysql_password}" -P"${mysql_port}" -h"${rip_eth0_master}" -e"show slave status\G" | grep "Seconds_Behind_Master: 0" > /dev/null 2>&1)
then
#如果主机能够访问，数据库同步无延迟，且本机就是主机，那么由本机绑定虚拟IP
if [ "${type}" = "master" ]
then
#如果本机为主机
function_bind_vip
function_vip_arping
echo "${date} 主机已绑定虚拟IP!(Type:1)" >> ${logfile}
else
#如果本机为备机
function_remove_vip
echo "${date} 备机已去除虚拟IP!(Type:2)" >> ${logfile}
fi
else
if [ "${type}" = "slave" ]
then
#如果本机为备机
function_rsync_slave_to_master
function_vip_arping
fi
fi
fi
else
#虚拟IP无法访问时，判断主机能否访问
if (curl -m 30 -G http://${rip_eth1_master}/ > /dev/null 2>&1) && (${mysql_bin} -u"${mysql_username}" -p"${mysql_password}" -P"${mysql_port}" -h"${rip_eth0_master}" -e"show slave status\G" > /dev/null 2>&1)
then
#如果主机能够访问，且本机就是主机，那么由本机绑定虚拟IP
if [ "${type}" = "master" ]
then
function_bind_vip
function_vip_arping
echo "${date} 主机已绑定虚拟IP!(Type:3)" >> ${logfile}
else
function_remove_vip
echo "${date} 备机已去除虚拟IP!(Type:4)" >> ${logfile}
fi
elif (curl -m 30 -G http://${rip_eth1_slave}/ > /dev/null 2>&1) && (${mysql_bin} -u"${mysql_username}" -p"${mysql_password}" -P"${mysql_port}" -h"${rip_eth0_slave}" -e"show slave status\G" > /dev/null 2>&1)
then
#如果主机不能访问而备机能够访问，且本机就是备机，那么由备机绑定虚拟IP
if [ "${type}" = "slave" ]
then
function_bind_vip
function_vip_arping
echo "${date} 备机已绑定虚拟IP!(Type:5)" >> ${logfile}
else
function_remove_vip
echo "${date} 主机已去除虚拟IP!(Type:6)" >> ${logfile}
fi
else
echo "${date} 主机、备机全部无法访问!(Type:7)" >> ${logfile}
fi
fi
#每次循环暂停20秒(即间隔20秒检测一次)
sleep 20
done