百度百科解释：

keepalived 是一个类似于 layer3, 4 & 7 交换机制的软件，也就是我们平时说的第 3 层、第 4 层和第 7 层交换。Keepalived 的作用是检测 web 服务器的状态，如果有一台 web服务器死机，或工作出现故障，keepalived 将检测到，并将有故障的 web 服务器从系统中剔除，当web服务器工作正常后 keepalived 自动将 web 服务器加入到服务器群中，这些工作全部自动完成，不需要人工干涉，需要人工做的只是修复故障的 web 服务器。

1、安装

• 方法一：yum 方式

方法二：源码包

1.mkdir /opt/software    #建立一个目录，用来存放软件包

2.cd /opt/software        #切换到该目录下

**3.wget https://www.keepalived.org/software/keepalived-2.0.20.tar.gz **  #联网下载，也可以windows下载好，上传进来

4.tar xvf keepalived-2.0.20.tar.gz

5.mv keepalived-2.0.20.tar.gz   /usr/local/src

6.cd /usr/local/src/keepalived-2.0.20

7.

yum install -y curl gcc openssl-devel libnl3-devel net-snmp-devel

yum -y install openssl openssl-devel

yum -y install libnl libnl-devel

yum -y install libnfnetlink-devel

8.完成后会在以下路径生成：

**/usr/local/keepalived/
/usr/local/keepalived/bin
/usr/local/keepalived/etc
/usr/local/keepalived/sbin

/usr/local/keepalived/share

---

/usr/local/keepalived/etc/keepalived/keepalived.conf
/usr/local/keepalived/etc/sysconfig/
/usr/local/keepalived/sbin/keepalived**

9.初始化启动

# keepalived 启动脚本变量引用文件，默认文件路径是 /etc/sysconfig/，也可以不做软链接，直接修改启动脚本中文件路径即可（安装目录下）
[root@localhost /]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/keepalived

将keepalived 主程序加入到环境变量（安装目录下）

[root@localhost /]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/keepalived

keepalived 启动脚本（源码目录下），放到 /etc/init.d/ 目录下就可以使用 service 命令便捷调用

[root@localhost /]# cp /usr/local/src/keepalived-2.0.20/keepalived/etc/init.d/keepalived /etc/init.d/keepalived

将配置文件放到默认路径下

[root@localhost /]# mkdir /etc/keepalived
[root@localhost /]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf

• 加为系统服务：           chkconfig   --add keepalived

• 开机启动：                  chkconfig keepalived on

• 查看开机启动的服务：chkconfig --list

• 启动、关闭、重启 :      service keepalived start|stop|restart

   卸载keeplived工作路径

[root@localhost /]# cd /usr/local/src/keepalived #源码所在目录（根据实际情况进入对应目录）
[root@localhost keepalived]#make uninstall

删除相关文件，有时系统版本差异，删除的时候，先查看该路径是否存在文件，以免删除错误，要仔细了。不要复制我的路径

#删除keepalived
[root@localhost /]# rm -f /usr/local/keepalived/sbin/keepalived
[root@localhost /]# rm -f /usr/local/keepalived/etc/rc.d/init.d/keepalived
[root@localhost /]# rm -f /usr/local/keepalived/etc/sysconfig/keepalived
[root@localhost /]# rm -rf /usr/local/keepalived/etc/keepalived
[root@localhost /]# rm -f /usr/local/keepalived/bin/genhash
[root@localhost /]# rm -rf /usr/local/keepalived
[root@localhost /]# rm -rf /etc/keepalived
[root@localhost /]# rm -f /etc/rc.d/init.d/keepalived
[root@localhost /]# rm -f /usr/sbin/keepalived 
[root@localhost /]# rm -f /etc/sysconfig/keepalived
[root@localhost /]# rm -f /etc/systemd/system/multi-user.target.wants/keepalived.service

测试是否卸载成功

[root@localhost /]# serive keepalived satrt
[root@localhost /]# systemctl start keepalived

当命令无效时，证明卸载成功。

相关操作命令

centOs：

      \[root@localhost /\]# systemctl start keepalived   -- 启动  
      \[root@localhost /\]# systemctl stop keepalived   --关闭  
      \[root@localhost /\]# ps aux|grep keepalived   --查看进程          

linux：
[root@localhost /]# service keepalived start -- 启动
[root@localhost /]# service keepalived stop --关闭
[root@localhost /]# ps aux|grep keepalived --查看进程