Nginx+keepalived高可用集群部署

1. 环境说明

2. Master部署

nginx安装见：https://blog.51cto.com/7965676/2629308
yum install -y keepalived
vim /etc/keepalived/keepalived.conf

global_defs {
    router_id NGINX_DEVEL
}
#定义脚本的名称为check_nginx
vrrp_script check_nginx {   
    #script后面可以直接接shell命令或一个可执行脚本
    script "/etc/keepalived/nginx_pid.sh"
    #定义执行间隔为2秒
    interval 2
    #失败次数为2次
    fall 2
    #检测1次成功就算成功
    rise 1
}
vrrp_instance nginx {   
    state MASTER
    interface ens33
    #定义发送vrrp广播的源地址
    mcast_src_ip 172.16.120.101
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    #执行监控的服务
    track_script {
        #引用VRRP脚本
        check_nginx
    }
    virtual_ipaddress {
        172.16.1.100/24
    }
}

3. Backup部署

nginx安装见：https://blog.51cto.com/7965676/2629308
yum install -y keepalived
vim /etc/keepalived/keepalived.conf

global_defs {
    router_id NGINX_DEVEL
}
vrrp_script check_nginx {
    script "/etc/keepalived/nginx_pid.sh"
    interval 2
    fall 2
    rise 1
}
vrrp_instance nginx {
  state BACKUP
  interface ens33
    mcast_src_ip 172.16.120.102
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_script {
        check_nginx
    }
    virtual_ipaddress {
        172.16.1.100/24
    }
}

4. 编写脚本

vim /etc/keepalived/nginx_pid.sh

#!/bin/bash
nginx_check () {
    nginxpid=`ps -C nginx --no-header |wc -l`
    if [ $nginxpid -eq 0 ];then
        /usr/local/nginx/sbin/nginx
        sleep 1
        nginxpid=`ps -C nginx --no-header |wc -l`
        if [ $nginxpid -eq 0 ];then
            systemctl stop keepalived
        fi
    fi
}
nginx_check

5. 启动服务

systemctl start keepalived
systemctl enable keepalived