使用Keepalived实现Nginx的双机热备功能

整体部署图

 

1、在两台服务器上部署并启动Nginx

    部署步骤参考 http://chenjumin.iteye.com/blog/2425443 

 

2、在Nginx服务器上步骤Keepalived

     1）执行 yum install -y keepalived 安装Keepalived

     2）在/etc/keepalived目录下创建编辑配置文件keepalived.conf

         主节点的配置文件

! Configuration File for keepalived

global_defs {
   router_id LVS126
}

vrrp_script chk_nginx {
    script "/etc/keepalived/nginx_check.sh"
    interval 2
    weight -5
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
	nopreempt
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.134.10
    }
}

 

       备节点的配置文件

! Configuration File for keepalived

global_defs {
   router_id LVS127
}

vrrp_script chk_nginx {
    script "/etc/keepalived/nginx_check.sh"
    interval 2
    weight -5
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.134.10
    }
}

 

     Nginx状态监测脚本文件nginx_check.sh

#!/bin/bash
A=`ps -C nginx --no-headers|wc -l`
if [ $A -eq 0 ];then
	/opt/software/nginx/sbin/nginx
	sleep 2
	if [ `ps -C nginx --no-headers|wc -l` -eq 0 ];then
		systemctl stop keepalived.service
	fi
fi

 

      3）启动Keepalived服务

         systemctl start keepalived.service

      4）查看服务状态

         systemctl status keepalived.service

 

3、修改keepalived的日志路径

      Keepalived默认所有的日志都是写入到/var/log/message下的，所以本文提供了一个调整Keepalived日志输出路径的方法。

      具体操作步骤如下：

            修改 /etc/sysconfig/keepalived

                  把KEEPALIVED_OPTIONS="-D" 修改为KEEPALIVED_OPTIONS="-D -d -S 0"

                  #其中-S指定syslog的facility

 

            设置syslog，修改/etc/rsyslog.conf，添加内容如下

                  local0.* /var/log/keepalived.log

 

             重启日志服务

                   systemctl restart rsyslog

 

             重启 keepalived

                   systemctl restart keepalived

 

              实时查看日志信息

                   tail -f /var/log/keepalived.log