Nginx+keepalived一主一备高可用

原创

康康的Babi 2021-07-23 15:55:05 博主文章分类：Linux ©著作权

文章标签 tomcat virtual router docker keepalived curl 文章分类 运维

©著作权归作者所有：来自51CTO博客作者康康的Babi的原创作品，请联系作者获取转载授权，否则将追究法律责任

Nginx+keepalived一主一备高可用

Nginx+keepalived一主一备高可用_virtual router

一、实验环境

准备两台NGINX环境的服务器

Nginx40.14	IPADDR=192.168.40.14
Nginx_40.15	IPADDR=192.168.40.15

准备一台tomcat服务器

Docker40.16	Tomcat8081	192.168.40.16:8081
	Tomcat8082	192.168.40.16:8082

二、配置环境

Nginx40.14
IPADDR=192.168.40.14  
Keepalived.conf配置：  
vrrp_instance VI_1  
state MASTER 
interface ens33  
virtual_router_id 17  
priority 150  
virtual_ipaddress 192.168.40.17

Nginx_40.15  
IPADDR=192.168.40.15 
Keepalived.conf配置： 
vrrp_instance VI_1 
state BACKUP 
interface ens33  
virtual_router_id 17 
priority 99 
virtual_ipaddress 192.168.40.17

Docker40.16 利用docker部署两个tomcat容器，并启动容器。

Tomcat8081	192.168.40.16:8081
Tomcat8082	192.168.40.16:8082

三、Keepalived安装部署

Keepalived下载地址https://www.keepalived.org/download.html

安装依赖环境

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

创建/data/keepalived,创建/software 软件存放目录

mkdir -p /data/keepalived

mkdir -p /software

上传安装包到/software
解压安装包

tar -zxvf keepalived-2.1.5.tar.gz

cd keepalived-2.1.5

./configure --prefix=/data/keepalived --sysconf=/etc

编译安装

make & manke install

Nginx+keepalived一主一备高可用_keepalived_02

确保依赖都安装的情况下更换keepalived低版本

四、进入安装后的路径

cd /data/keepalived/

创建软连接

ln -s sbin/keepalived /sbin/

覆盖软连接

ln -snf sbin/keepalived /sbin

复制运行命令

cp/software/keepalived-.1.5/keepalived/etc/init.d/keepalived /etc/init.d
chkconfig --add keepalived

添加到系统服务

chkconfig keepalived on

启动服务

service keepalived start

查看启动状态

service keepalived status

五、修改keepalived 的配置

Master配置

vim /etc/keepalived/    #（最小配置）

! Configuration File for keepalived
global_defs {     
     router_id NGINX   
  }        

vrrp_instance VI_1 { 
      state MASTER
      interface ens33 
      virtual_router_id 17
      priority 150 
      advert_int 1
      authentication { 
      auth_type PASS
        auth_pass 1111
      } 

     virtual_ipaddress {
        192.168.40.17/24
      }

  }

Backup配置

vim /etc/keepalived/    #（最小配置）

! Configuration File for keepalived
global_defs {
    router_id NGINX
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 17
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.40.17/24
    }
}

六、启动nginx

/usr/local/nginx/sbin/nginx

七、启动keepalived

service keepalived start

八、查看网卡是否获取到虚拟IP

Ip add

Nginx+keepalived一主一备高可用_docker_03

九、验证试验

curl http://192.168.40.17

Nginx+keepalived一主一备高可用_virtual router_04

十、验证冗余

手动停止 nginx服务

/usr/local/nginx/sbin/nginx –s stop

网页无法开启

手动停止keepalived服务

service keepalived stop  网页正常

十一、利用脚本实现自动切换

Keepalived检测nginx运行状态的脚本

#!/bin/bash
A=`ps -C nginx  --no-header|wc -l`    #判断nginx的服务进程数并统计
if [ $A -eq 0  ];then    #假如数量为0则执行以下脚本  /usr/local/nginx/sbin/./nginx
sleep 2    #进程休眠2秒
if [ `ps -C  nginx --no-header|wc -l` -eq 0 ];then    #假如nginx服务进程总数还是0则执行以下脚本
killall  keepalived    #结束keepalived所有进程
fi
fi

修改keepalived.conf配置

Nginx-keepalived-MASTER

! Configuration File for keepalived
global_defs {
router_id NGINX     #路由标识同一个主备必须相同
}
vrrp_script chk_nginx {
            script "/root/chk_nginx.sh"     #检测脚本的路径                 interval 2     #脚本执行间隔
            weight -5     #失败一次自己优先级降低5
}

vrrp_instance VI_1 {
     state MASTER    #节点状态，主节点为MASTER，备节点为BACKUP          interface ens33    #vip绑定的网络接口 
     virtual_router_id 17    #虚拟路由ID，方便记录可以使用IP最后一位VRID区间是0~255正证书
     priority 100   #节点优先级，优先级是0~255正整数
     advert_int 1
     authentication {    #认证
         auth_type PASS    #明文认证
         auth_pass 1111    #认证密码
     }
     
     virtual_ipaddress {
             192.168.40.17/24   #虚拟IP/掩码
     }
     
         track script {   #追踪脚本
               chk_nginx
         }
}

2) Nginx-keepalived-BACKUP

! Configuration File for keepalived
global_defs {
router_id NGINX   #路由标识同一个主备必须相同
}

vrrp_instance VI_1 {
     state BACKUP   #节点状态，主节点为MASTER，备节点为BACKUP          interface ens33   #vip绑定的网络接口
     virtual_router_id 17   #虚拟路由ID，方便记录可以使用IP最后一位VRID区间是0~255正证书
     priority 99    #节点优先级，优先级是0~255正整数
     advert_int 1
     authentication {   #认证
         auth_type PASS   #明文认证
         auth_pass 1111   #认证密码
     }
     
     virtual_ipaddress {
             192.168.40.17/24   #虚拟IP/掩码
     }
  }
}