keepalived主从模式监测nginx

不念不忘少年蓝@ 2023-06-25 04:58 15阅读 0赞

## 一、环境说明 ##

VirtualBox6.1  
CenOS7  
Nginx  
keepalived-1.1.20.tar.gz

## 二、IP配置 ##

主Keepalived服务器IP地址：10.0.2.4  
备Keepalived服务器IP地址：10.0.2.5  
虚拟Keepalived服务器IP地址：10.0.2.6

## 三、下载地址 ##

**http://www.keepalived.org/software/** 可以选择自己需要的版本。

## 四、安装步骤 ##

1、下载好安装包，可使用xshell软件连接虚拟机，将压缩包上传至/home目录。或者直接在虚拟机里执行命令下载：wget http://www.keepalived.org/software/keepalived-1.1.20.tar.gz（如果提示没有wget命令，安装即可：yum install wget）。  
2、解压keepalived（两个虚拟机都需要做，步骤一致）：

[root@localhost]# cd /home 
    [root@localhost home]# tar -zxvf keepalived-1.1.20.tar.gz 
    [root@localhost home]# cd keepalived-1.1.20
    [root@localhost keepalived-1.1.20]# ln -s /usr/src/kernels/2.6.9-78.EL-i686/usr/src//linux
    [root@localhost keepalived-1.1.20]# ./configure

执行完./configure后会显示：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70]  
3、编译安装:

[root@localhost keepalived-1.1.20]# make && make install

4、修改配置文件路径：

[root@localhost keepalived-1.1.20]# cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
    [root@localhost keepalived-1.1.20]# cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
    [root@localhost keepalived-1.1.20]# mkdir /etc/keepalived
    [root@localhost keepalived-1.1.20]# cp /usr/local/etc/keepalived/keepalived.conf/etc/keepalived/ 
    [root@localhost keepalived-1.1.20]# cp /usr/local/sbin/keepalived /usr/sbin/

5、设置服务开机启动:

[root@localhost keepalived-1.1.20]# vi /etc/rc.local

在最后一行加上： /etc/init.d/keepalived start

## 五、配置流程 ##

1、配置 主：

[root@localhost keepalived-1.1.20]# vi /etc/keepalived/keepalived.conf

![在这里插入图片描述][20191226164841532.png]  
2、配置 备：

[root@localhost keepalived-1.1.20]# vi /etc/keepalived/keepalived.conf

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 1]  
3、启动服务：  
![20191226115550323.png][]

## 六、验证测试 ##

1、创建监控双机nginx状态的脚本：`vi /opt/check_nginx.sh`  
写入以下代码：

#!/bin/sh
    A=`ps -C nginx --no-header |wc -l`
    if [ $A -eq 0 ];then  #如果nginx没在运行
       systemctl start nginx.service  #启动nginx
       sleep 2
       if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then  #如果无法启动
    	killall keepalived  #杀死keepalived进程
       fi
    fi

2、安装psmisc，因为脚本用到了killall命令，最小化安装的centos没有，所以要安装一下：yum -y install psmisc。  
3、再次编辑keepalived配置文件：

vi /etc/keepalived/keepalived.conf

插入第一段：

vrrp_script check_nginx
    { 
       script "/root/check_nginx.sh"
       interval 2
       weight 2
    }

再插入第二段：

track_script 
    {  
            check_nginx
    }

它们的位置如下：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 2]  
4、备用机与此步骤一样。  
5、启动keepalived服务,并开机自启。

systemctl start keepalived.service
    systemctl enable keepalived.service

6、测试：  
修改一下主机nginx的欢迎界面，以和备用机区分：添加单词Master和Backup：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 3]  
7、在浏览器输入虚拟机ip：81，停掉主机服务器的nginx，systemctl stop nginx.service。刷新页面会发现没有变化，这是因为keepalived检测到nginx挂了，会通过check\_nginx.sh脚本自动启动nginx。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 4]  
8、当手动停止主机的keepalived：systemctl stop keepalived.service  
会发现页面标题的Master没有了，就变成了Backup。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 5]  
此时才算是配置成功了。

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[20191226164841532.png]: https://img-blog.csdnimg.cn/20191226164841532.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20191226164646219.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5,size_16,color_FFFFFF,t_70
[20191226115550323.png]: https://img-blog.csdnimg.cn/20191226115550323.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20191228175341381.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5,size_16,color_FFFFFF,t_70
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5_size_16_color_FFFFFF_t_70 5]: https://img-blog.csdnimg.cn/20191228175639693.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MDcxNTk5,size_16,color_FFFFFF,t_70