Nginx+keepalived(高可用主备模式)

环境：centos6.7

准备：两台服务器（虚拟机）、两台应用（Tomcat）、Nginx、keepalived

server1:192.168.237.128 安装上Nginx和keepalived VIP 192.168.237.10（同网段）

server2:192.168.237.129 安装上Nginx和keepalived

安装keepalived ： yum install keepalived

keepalived 配置文件路径 /etc/keepalived/keepalived.conf

1.分别开启NginxA和NginxB ，使两台Nginx都能分发请求至TA、TB

keepalivedA配置文件

! Configuration File for keepalived

global_defs {
router_id 192.168.237.128
}

vrrp_script chk_nginx { 
script "/operation/nginx_check.sh" 
interval 5 
weight -5 
}

vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 110
authentication {
auth_type PASS
auth_pass 1111
}

virtual_ipaddress {
192.168.237.10
}

track_script {
chk_nginx 
}
}

启动keepalivedA : service keepalived start;启动成功keepalivedA后查看 ip addr keepalived日志路径 /var/log/messages

keepalivedB文件配置

! Configuration File for keepalived

global_defs {
router_id 192.168.237.129
}

vrrp_script chk_nginx { 
script "/operation/nginx_check.sh" 
interval 5 
weight -5 
}


vrrp_instance VI_1 {
state BACKUP  #备机
interface eth0
virtual_router_id 51
priority 100  #优先级  小于主机
authentication {
auth_type PASS
auth_pass 1111
}

virtual_ipaddress {
192.168.237.10
}

track_script {
chk_nginx 
}
}

检测Shell脚本 nginx_check.sh

#!/bin/bash
A=`ps -C nginx –no-header |wc -l`
if [ $A -eq 0 ];then
/usr/local/nginx/sbin/nginx
sleep 2
if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then
killall keepalived
fi
fi

启动keepalivedA：根据日志可知，配置生效检测脚本已生效