参考地址：http://blog.51cto.com/songky/1964672

安装编译所必要的依赖

yum install gcc openssl-devel libnl libnl3-devel libnfnetlink-devel

下载并编译

wget [http://www.keepalived.org/software/keepalived-1.3.5.tar.gz](http://www.keepalived.org/software/keepalived-1.3.5.tar.gz)
tar zxf keepalived-1.3.5.tar.gz
cd keepalived-1.3.5
./configure --prefix=/usr/local/keepalived --with-init=SYSV  --不指定的话，默认不生成RECL6的启动脚本
make && make install

将文件拷贝到特定的目录

cp /usr/local/keepalived/sbin/keepalived /usr/sbin/
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
cp -p /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
mkdir /etc/keepalived
cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
chkconfig --add keepalived
chkconfig --list keepalived
chkconfig  keepalived on
chmod +x /etc/init.d/keepalived

启动服务

service tomcat start
service keepalived start

检查主从切换日志：

tail -f /var/log/messages

重点说明：

一、重启keepalived服务后，ping不通vip地址？

vim /etc/keepalived/keepalived.conf

把下面这个注释就可以了

vrrp_strict

二、vip切换及恢复原则：

1. 切换：master服务器的tomcat服务停止，则master上的keepalived会自动停止， vip漂移到backup服务器
2. 恢复：master服务器修复完毕后， 请分别启动tomcat和keepalived，则vip会自动漂移到master服务器

配置文件参考

1. keepalived.master.conf

global_defs {
    notification_email {
        root@localhost
    }
    notification_email_from root@localhost
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id LVS_DEVEL
    vrrp_skip_check_adv_addr
    # vrrp_strict
    vrrp_garp_interval 0
    vrrp_gna_interval 0
}

vrrp_script chk_http_port {
    script "/etc/keepalived/check-tomcat.sh"
    interval 1
    weight 2
}

vrrp_instance VI_1 {
    state Primary
    interface eno1
    virtual_router_id 51
    priority 99          #此处不同,要低于master
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_interface {
        eno1
    }
    track_script {
        chk_http_port
    }
    virtual_ipaddress {
        172.20.30.33
    }
}

2. keepalived.slaver.conf

global_defs {
    notification_email {
        root@localhost
    }
    notification_email_from root@localhost
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id LVS_DEVEL
    vrrp_skip_check_adv_addr
    # vrrp_strict
    vrrp_garp_interval 0
    vrrp_gna_interval 0
}
    
vrrp_script chk_http_port {
    script "/etc/keepalived/check-tomcat.sh"
    interval 1
    weight -2
}

vrrp_instance VI_1 {
    state Secondary
    interface eno1
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_interface {
        eno1
    }
    track_script {
        chk_http_port
    }
    virtual_ipaddress {
        172.20.30.33
    }
}