keepalived+nginx实现nginx高可用

w12dw

前期准备：
1、实验拓扑图

2、地址规划

Master	10.10.0.224(VIP:10.10.0.220)	keepalived、nginx
Backup	10.10.0.226(VIP:10.10.0.220)	keepalived、nginx
Real Server 1（apache1）	10.10.0.225	httpd
Real Server 2（apache2）	10.10.0.221	httpd

一、安装keepalived和nginx
Master和Backup分别安装:
1、安装keepalived
[iyunv@node1 ~]# yum install keepalived -y
2、配置repo源
[iyunv@node1 ~]# vim /etc/yum.repos.d/nginx.repo
[nginx]

name=nginx repo

baseurl=http://nginx.org/packages/centos/6/$basearch/

gpgcheck=0

enabled=1

3、安装ngxin

[iyunv@node1 ~]# yum install nginx -y

4、Master修改
(1).修改keepaliaved配置文件

[iyunv@node1 ~]# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
[iyunv@node1 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
   notification_email {
        root@localhost
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS1
}
vrrp_script chk_nginx{

        script "killall -0 nginx"
        interval 1
        weight -2
        fall 2
        rise 2
}
vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.10.0.220 dev eth0 label eth0:0
}
track_script {
        chk_nginx
}
}
(3).拷贝一份配置文件到Backup服

[iyunv@node1 ~]# scp -r /etc/keepalived/keepalived.conf root@10.10.0.226:/etc/keepalived/
[iyunv@node1 ~]# scp -r /etc/nginx/nginx.conf root@10.10.0.226:/etc/nginx/
(4).开启服务并开机自动启动
[iyunv@node1 ~]# service keepalived restart
[iyunv@node1 ~]# service nginx restart
[iyunv@node1 ~]# chkconfig keepalived on
[iyunv@node1 ~]# chkconfig nginx on
5、Backup修改
(1).修改keepalived配置文件
[iyunv@node2 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {

   notification_email {
        root@localhost
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS2     #修改唯一标识
}
vrrp_script chk_nginx{

        script "killall -0 nginx"
        interval 1
        weight -2
        fall 2
        rise 2
}
vrrp_instance VI_1 {

    state BACKUP
    interface eth0
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.10.0.220 dev eth0 label eth0:0
}
track_script {

        chk_nginx
}
}

(2).开启服务并开机自动启动

[iyunv@node2 ~]# service keepalived restart

[iyunv@node2 ~]# service nginx restart

[iyunv@node2 ~]# chkconfig keepalived on

[iyunv@node2 ~]# chkconfig nginx on

6、Real Server 1

(1).安装httpd

[iyunv@realserver1]# yum install httpd -y

(2).建立测试页

[iyunv@realserver1]# vim /var/www/html/index.html

<h1>real server 1</h1>

(3).开启服务

[iyunv@realserver1]# service httpd restart   

[iyunv@realserver1]# chkconfig httpd on

(4).测试

7、Real Server 2

(1).安装httpd

[iyunv@realserver2]# yum install httpd -y

(2).建立测试页

[iyunv@realserver2]# vim /var/www/html/index.html

<h1>real server 2</h1>

(3).开启服务

[iyunv@realserver2]# service httpd restart   

[iyunv@realserver2]# chkconfig httpd on

(4).测试

8、nginx实现后端real server的负载均衡，在Master上配置

(1).修改nginx配置文件

[iyunv@node1 ~]# cp /etc/nginx/nginx.conf /etc/nginx/nginx.conf.bak

[iyunv@node1 ~]# vim /etc/nginx/nginx.conf

user  nginx;

worker_processes  1;

error_log  /var/log/nginx/error.log warn;

pid        /var/run/nginx.pid;

events {

    worker_connections  1024;

}

http {

    include       /etc/nginx/mime.types;

    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '

                      '$status $body_bytes_sent "$http_referer" '

                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;

    #tcp_nopush     on;

    keepalive_timeout  65;

    #gzip  on;

    upstream apacheweb {

        server 10.10.0.225:80 max_fails=3 fail_timeout=2s;

        server 10.10.0.221:80 max_fails=3 fail_timeout=2s;

        server 10.10.0.224:8080 backup;    #sorry server,当两个realserver全挂掉后显示。

    }

server {
  listen 8080;
  location / {
        root /usr/share/nginx/html/a;
        index index.html index.html;
#        proxy_pass http://apacheweb;
    }
}

server {

    listen       80;

    server_name  localhost;

    #charset koi8-r;

    #access_log  /var/log/nginx/log/host.access.log  main;

    location / {

        root   /usr/share/nginx/html;

        index  index.html index.htm;

    }

    location ~ \.(html|htm|gif|jpg|jpeg|bmp|png|ico|txt|js|css)$ {

        root        /var/www/html;  #此处定义后端服务器网页存放路径   

        proxy_pass   http://apacheweb;

    }

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html

    error_page   500 502 503 504  /50x.html;

    location = /50x.html {

        root   /usr/share/nginx/html;

    }

｝

(2).拷贝一份配置文件到Backup

[iyunv@node1 ~]# scp -r /etc/nginx/nginx.conf root@10.10.0.226:/etc/nginx/

(3).重启nginx服务

[iyunv@node1 ~]# service nginx restart

[iyunv@node2 ~]# service nginx restart

9、测试

(1).在浏览器中输入vip地址

刷新浏览器之后

(2).模拟故障：

[iyunv@realserver1]# service httpd stop

停掉real server 1的apache服务,刷新浏览器发现访问的内容一直是real server2的内容

启用之后real server 1会被加入会话。反之停掉real server 2,访问的内容就一直是real server 1啦

当real server 1和real server 2全部挂掉之后，则显示10.10.0.224：8080虚拟主机里的内容。任何一个real server回归后，则显示正常。