部署 Keepalived 及配置 VIP

部署 Keepalived 及配置 VIP

1 准备工作

1.1 服务器准备

此处在 MySQL 集群节点上进行 Keepalived 的安装，一起实现负载均衡和 MySQL 的高可用，节点规划如下：

Keepalived-1 节点，IP 为 10.1.11.187
Keepalived-2 节点，IP 为 10.1.11.189

其他信息：

VIP：10.1.11.137

1.2 软件准备

可以在 Keepalived 官网下载对应的安装包，此处下载的是 keepalived-2.2.7.tar.gz。

wget --no-check-certificate https://www.keepalived.org/software/keepalived-2.2.7.tar.gz

2 安装 Keepalived

在两个节点上分别执行以下命令安装 Keepalived：

# 安装依赖包
yum install -y gcc-c++ pcre-devel openssl-devel popt-devel gcc automake autoconf libtool make ca-certificates
tar zxvf keepalived-2.2.7.tar.gz -C /opt
cd /opt/keepalived-2.2.7
./configure --prefix=/usr/local/keepalived
make && make install

3 配置系统服务

在两个节点上分别执行以下命令：

cp /usr/local/keepalived/etc/sysconfig/keepalived  /etc/sysconfig/keepalived
cp /usr/local/keepalived/sbin/keepalived /usr/sbin/keepalived
cp /opt/keepalived-2.2.7/keepalived/etc/init.d/keepalived /etc/init.d/keepalived
mkdir -p /etc/keepalived

加为系统服务且开机自启动：

chkconfig --add keepalived
chkconfig keepalived on

4 编写 Keepalived 切换脚本

在两个节点上执行以下命令创建 Keepalived 切换脚本：

cat <<EOF >> /usr/local/keepalived/down.sh
#!/bin/bash
pkill keepalived
EOF
# 赋予切换脚本执行权限
chmod +x /usr/local/keepalived/down.sh

5 配置 Keepalived

5.1 配置 Keepalived-1 节点

将 Keepalived-1 上的 Keepalived 配置文件 /etc/keepalived/keepalived.conf 修改为以下内容：

! Configuration File for keepalived
global_defs {
   router_id DE_HA
}
vrrp_instance VI_1 {
    state MASTER
    interface ens192
    virtual_router_id 51
    priority 100
    advert_int 1
    #本机 ip
    unicast_src_ip 10.1.11.187
    unicast_peer {
        #对端 ip
        10.1.11.189
}
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.1.11.137
    }
}
virtual_server 10.1.11.137 3306 {
    delay_loop 2
    persistence_timeout 50
    protocol TCP
    real_server 10.1.11.187 3306 {
        weight 3
        notify_down /usr/local/keepalived/down.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
virtual_server 10.1.11.137 80 {
    delay_loop 2
    persistence_timeout 50
    protocol TCP
    real_server 10.1.11.187 80 {
        weight 3
        notify_down /usr/local/keepalived/down.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

注意：

配置文件中的 “interface ens192”，需要视具体环境设置对应的网卡，如 “eth0” 等；
注意配置文件中的 “state MASTER”、”priority 100”。

5.2 配置 Keepalived-2 节点

将 Keepalived-2 节点上的 Keepalived 配置文件 /etc/keepalived/keepalived.conf 修改为以下内容：

! Configuration File for keepalived
global_defs {
   router_id DE_HA
}
vrrp_instance VI_1 {
    state BACkUP
    interface ens192
    virtual_router_id 51
    priority 50
    advert_int 1
    #本机ip
    unicast_src_ip 10.1.11.189
    unicast_peer {
        #对端ip
        10.1.11.187
    }
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.1.11.137
    }
}
virtual_server 10.1.11.137 3306 {
    delay_loop 2
    persistence_timeout 50
    protocol TCP
    real_server 10.1.11.189 3306 {
        weight 3
        notify_down /usr/local/keepalived/down.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
virtual_server 10.1.11.137 80 {
    delay_loop 2
    persistence_timeout 50
    protocol TCP
    real_server 10.1.11.189 80 {
        weight 3
        notify_down /usr/local/keepalived/down.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}