一键安装keepalive

启动应用程序后
将下载的keepalive*.tar.gz版本与该脚本放在同一目录。
执行命令一键安装，如：
sh ins_keep_app.sh keepalived-2.2.2.tar.gz

注意

1. 部分变量需要根据自身情况修改脚本，不修改将提示输入，如：

ifname=''   # 网卡名
rip=''      # 网卡实IP
vip=''      # 浮动IP
port=''     # 监控端口
priority='' # 优先级 0-100

2. keepalive的安装需要依赖部分软件包。需要提前配置好yum

ins_keep_app.sh

#!/bin/bash
# 说明：
# 	监控应用端口是否正常，如果不正常则杀keepalive进程，实现切换。
#

# 变量设置,请根据实际情况变更。
ifname=''   # 网卡名
rip=''      # 网卡实IP
vip=''      # 浮动IP
port=''     # 监控端口
priority='' # 优先级 0-100

if [ ! $ifname ];then 
    read -p "网卡名:"     ifname
fi
if [ ! $rip ];then 
    read -p "真实IP地址:" rip
fi
if [ ! $vip ];then 
    read -p "浮动IP地址:" vip
fi
if [ ! $port ];then 
    read -p "监控端口:"   port
fi
if [ ! $priority ];then 
    read -p "节点优先级(0-100):" priority
fi


# 判断是否有参数
if [ x$1 == x ];then
    echo "Usage: sh $0 keepalive_filename"
    exit 1
fi

# 安装依赖包
yum install -y gcc openssl openssl-devel libnl libnl-devel libnl3 libnl3-devel
filename=$1
tar -xvf $filename
cd ${filename%.*.*}
./configure --prefix=/usr/local/keepalived
make && make install
confdir=/etc/keepalived
if [ ! -d $confdir ];then
    mkdir $confdir
fi
cat > /etc/keepalived/keepalived.conf << EOF
global_defs {  
     router_id HA
     script_user root            #下面的脚本由谁执行
     enable_script_security
     }
vrrp_instance VI_1 {
     state BACKUP
     interface $ifname    #网卡接口
     virtual_router_id 20
     priority $priority       #优先级
     advert_int 1
     nopreempt
     authentication { 
     auth_type PASS
     auth_pass 1111
     }
     virtual_ipaddress {  
     $vip  # VIP 地址
     }  
     }  
virtual_server $vip $port {  # VIP 地址+端口
     delay_loop 2   	#每个2秒检查一次real_server状态  
     lb_algo wrr   	#LVS算法
     lb_kind DR    #LVS模式  
     persistence_timeout 60   #会话保持时间  
     protocol TCP  
     real_server $rip $port {  # 真实IP地址+端口
     weight 3
     notify_down /etc/keepalived/kill_keepalive.sh  #检测到服务down后执行的脚本  
     TCP_CHECK {  
     connect_timeout 10    #连接超时时间  
     retry 3               #重连次数  老版本为: nb_get_retry
     delay_before_retry 3   #重连间隔时间  
     connect_port $port   #健康检查端口  
     }  
     } 
     }
EOF

cat > /etc/keepalived/kill_keepalive.sh  <<EOF
#!/bin/bash
pkill keepalived
EOF
chmod +x /etc/keepalived/kill_keepalive.sh

systemctl restart keepalived
systemctl enable keepalived
systemctl status keepalived

如果不需要监控APP程序，只实现宕机情况下的IP切换，使用如下脚本
ins_keep_vip.sh

#!/bin/bash
# 说明：
#     实现虚拟IP的挂载，节点故障后自动切换到备机。
# 变量设置
# 请根据实际情况修改如下变量
ifname='eth0'
priority='100'
vip='192.168.10.20'

# 判断是否有参数
if [ x$1 == x ];then
    echo "Usage:$0 keepalive_filename"
    exit 1
fi

# 安装依赖包
yum install -y gcc openssl openssl-devel libnl libnl-devel libnl3 libnl3-devel
filename=$1
tar -xvf $filename
cd ${filename%.*.*}
./configure --prefix=/usr/local/keepalived
make && make install
confdir=/etc/keepalived
if [ ! -d $confdir ];then
    mkdir $confdir
fi
cat >>/etc/keepalived/keepalived.conf << EOF
global_defs {  
     router_id HA
     }

vrrp_instance VI_1 {
     state BACKUP
     interface $ifname    #网卡接口
     virtual_router_id 20
     priority $priority       #优先级
     advert_int 1
     nopreempt
     authentication { 
     auth_type PASS
     auth_pass 1111
     }
     virtual_ipaddress {  
     $vip  # VIP 地址
     }  
     }  
EOF
systemctl restart keepalived
systemctl enable keepalived
systemctl status keepalived