欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页

Keepalived配合Nginx搭建高可用服务器集群

程序员文章站 2024-03-21 09:24:52
...

系统

两台Nginx:

CentOS6.5 x86_64

两台tomcat:

CentOS6.5 x86_64

1.拓扑

Keepalived配合Nginx搭建高可用服务器集群

机器IP

安装软件

角色

虚拟ip

描述

192.168.15.132

Nginx、keepalived

Nginx主机

192.168.15.135

反向代理到tomcat1和tomcat2

192.168.15.133

Nginx、keepalived

Nginx备机

主机挂了切换虚拟ip 192.168.15.135

反向代理到tomcat1和tomcat2

192.168.15.128

Tomcat

Tomcat1

 

192.168.15.30

Tomcat

Tomcat2

 

IP地址

nginx(主LB):192.168.15.132

nginx(备LB):192.168.15.133

VIP地址:192.168.15.135

Real1的IP:192.168.15.128

Real2的IP:192.168.15.30

2.安装keepalived和nginx

在两台nginx服务器张安装keepalived:

wget http://www.keepalived.org/software/keepalived-1.2.15.tar.gz
tar -zxvf keepalived-1.2.15.tar.gz
cd keepalived-1.2.15
./configure --sysconf=/etc/  --with-kernel-dir=/usr/src/kernels/2.6.32-573.8.1.el6.x86_64
make && make install
ln -s /usr/local/sbin/keepalived  /sbin/  

ln -s这一步很重要

不执行ln -s会报错“Starting keepalived: /bin/bash: keepalived: command not found”

service keepalived start

上述步骤也可以直接通过yum –y install keepalived 来代替,不同安装方式而已,不是重点

3.配置keepalived和nginx

二台Nginx上keepalived.conf配置文件如下

user  nobody;
worker_processes  1;
error_log  /usr/local/nginx/logs/error.log notice;
pid        /usr/local/nginx/logs/nginx.pid;
worker_rlimit_nofile 51200;
events {
    use epoll;
    worker_connections  51200;
}
http {
    include       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  logs/access.log  main;
    server_names_hash_bucket_size 128;
    client_header_buffer_size 32k;
    large_client_header_buffers 4 32k;
    client_max_body_size 8m;
    sendfile        on;
    tcp_nopush     on;
    server_tokens off;
    keepalive_timeout  60;
    fastcgi_connect_timeout 300;
    fastcgi_send_timeout 300;
    fastcgi_read_timeout 300;
    fastcgi_buffer_size 64k;
    fastcgi_buffers 4 64k;
    fastcgi_busy_buffers_size 128k;
    fastcgi_temp_file_write_size 128k;
    gzip  on;
    upstream backend
    {
    server 192.168.15.128;
    server 192.168.15.130;
    }
    server {
        listen       80;
        server_name  192.168.15.135;
        location / {
            root   html;
            index  index.php index.html index.htm;
            proxy_redirect off;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            #后端的Web服务器可以通过X-Forwarded-For获取用户真实IP
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_pass http://backend;
        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
         
        location /nginx_status {
            stub_status on; 
            auth_basic "NginxStatus";
            auth_basic_user_file /usr/local/nginx/htpasswd;
            #allow 127.0.0.1;
            #deny all;
        }
        location ~* \.(ini|docx|txt|doc|pdf)$ {
        #禁止访问文档性文件
        root /usr/share/nginx/html;
        deny all;
        }
        location ~ .*\.(gif|jpg|jpeg|png|bmp|swf|js|html|htm|css)$ {
        root /home/image;
        proxy_store on;
        proxy_store_access user:rw group:rw all:rw;
        proxy_temp_path /home/image;
        if ( !-e $request_filename) {
           proxy_pass  http://backend;
        }
    }
}
}

配置完成后分别service keepalived start启动。检验keepalived配置是否成功

两台keepalived的配置如下:可以看出两者之间的区别仅仅是主备的权重不同,主为100备为66,其余一些有作用的配置已经用红色标注

主:

global_defs {
   notification_email {
     aaa@qq.com
   }
   notification_email_from aaa@qq.com 
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_MASTER
}
vrrp_script chk_http_port {
script "/usr/local/src/check_nginx_pid.sh"
interval 2                           #(检测脚本执行的间隔)
weight 2
}
vrrp_instance VI_1 {
   #state MASTER
    state BACKUP
    nopreempt                       
    #设置非抢占模式时,修改“state MASTER”为“state BACKUP”,添加“nopreempt“
    interface bond0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
}
track_script {
chk_http_port            #(调用检测脚本)
}
    virtual_ipaddress {
        192.168.15.135
    }
}

备: 

global_defs {
   notification_email {
     aaa@qq.com
   }
   notification_email_from aaa@qq.com 
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_BACKUP
}
vrrp_script chk_http_port {
script "/usr/local/src/check_nginx_pid.sh"
interval 2                           #(检测脚本执行的间隔)
weight 2
}
vrrp_instance VI_1 {
    state BACKUP
    interface bond0
    virtual_router_id 51
    priority 66
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
}
track_script {
chk_http_port            #(调用检测脚本)
}
    virtual_ipaddress {
        192.168.15.135
    }
}

以下是针对nginx状态进行检测的脚本,第一次nginx服务死掉时,会重新启动,如果Nginx服务无法正常启动,则杀掉keepalived进程

vim  /usr/local/src/check_nginx_pid.sh
#!/bin/bash
A=`ps -C nginx --no-header |wc -l`        
if [ $A -eq 0 ];then                            
      /usr/local/nginx/sbin/nginx        
      if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then  
              killall keepalived                    
      fi
fi

Ok,开始nginx负载均衡测试,停掉其中一台的任何服务,不影响整个系统的运作。

4.测试

依次启动两个tomcat=》启动两个nginx=》启动两个keepalived,查看主机上是否有虚拟ip 192.168.15.135

在192.168.15.128和192.168.15.30上分别解压修改tomcat的index页面:

vi webapps/ROOT/index.jsp

修改页面html部分

<html>
    <head>
    </head>
    <body>
SessionID:<%=session.getId()%>
<br/>
SessionIP:<%=request.getServerName()%>
<br/>
<h1>tomcat1 page</h1>
</body>
</html>

这样可以通过访问index来判断访问是不是轮询的

通过虚拟ip访问nginx,看页面是不是轮询两个tomcat

将主机的nginx进程kill掉,看看vip是不是切换到备机器上了

访问虚拟ip是不是还能轮询访问tomcat

转载于:https://my.oschina.net/liuyuantao/blog/1507432