centos7.1实现nginx+keepalived 负载均衡+高可用

一.环境

centos7.1操作系统      

二.基础架构

nginx1.10.2+keepalived1.2.13               192.168.2.65

nginx1.10.2+keepalived1.2.13               192.168.2.66

web1
192.168.2.83

web2
192.168.2.84

虚拟IP
192.168.2.67

三.安装nginx+keepalived

               

安装网易云镜像和nginx的镜像，然后使用yum
install -y nginx keepalived

四.配置nginx和keepalived

nginx主 从配置一样，把原来的/etc/nginx/conf.d/default.conf 删除，重新创建一个proxy.conf，把下面配置拷贝进去就行。

vi /etc/nginx/conf.d/proxy.conf

upstream web {

    #ip_hash;

        server 192.168.2.83:80;   #默认为rr轮询，如需解决session的问题采有哈希（ip_hash)模块。

        server 192.168.2.84:80;

}

        server {

        listen 80;

        index index.php index.html index.htm;

        location / {

        proxy_pass http://web;
        proxy_set_header X-Real-IP $remote_addr;

        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

}

}

主keepalived配置，直接把原有的配置文件删除，拷贝下面的进去。

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {

   router_id master

}

vrrp_script chk_nginx {

    script "/etc/keepalived/nginx_check.sh"

    interval 2

    weight -20

}

vrrp_instance VI_1 {

    state MASTER

    interface em1

    virtual_router_id 51

    mcast_src_ip 192.168.2.65

    priority 100

    nopreempt

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_script {

        chk_nginx

 }

    virtual_ipaddress {

        192.168.2.67

    }

}

从keepalived配置，删除原有的文件内容，拷贝下面内容。

! Configuration File for keepalived

global_defs {

   router_id slave1

}

vrrp_script chk_nginx {

    script "/etc/keepalived/nginx_check.sh"

    interval 2

    weight -20

}

vrrp_instance VI_1 {

    state BACKUP

    interface em1

    virtual_router_id 51

    mcast_src_ip 192.168.2.66

    priority 90

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_script {

        chk_nginx

    }

    virtual_ipaddress {

        192.168.2.67

    }

}

两个web页面配置

yum install httpd -y

service httpd start

配置检测nginx服务脚本

vi /etc/keepalived/nginx_check.sh  

#!/bin/bash

A=`ps -C nginx –no-header |wc -l`

if [ $A -eq 0 ];then

    /usr/local/nginx/sbin/nginx

    sleep 2

    if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then

        killall keepalived

    fi

fi

五.配置完成后，启动服务

systemctl nginx start

systemctl keepalived start

六.测试

65单独正常

66单独正常

访问67正常

虚拟IP在65上面

现在关闭65的nginx服务，65失效，但访问67正常，说明整体还在正常工作。虚拟IP漂移到66上面，推选66为主。

反之，关闭66主的还在服务。测试完成