基于nginx的tomcat负载均衡和集群

要集群tomcat主要是解决SESSION共享的问题，因此我利用memcached来保存session，多台TOMCAT服务器即可共享SESSION了。

你可以自己写tomcat的扩展来保存SESSION到memcached。

这里推荐使用memcached-session-manager这个开源项目（http://code.google.com/p/memcached-session-manager/ ），下面简称msm。

 

如何安装nginx、memcached、tomcat这些就不多说了。

 

先说明一下测试环境:

tomcat1、nginx、memcached安装在192.168.1.11

tomcat2安装在192.168.1.101

 

下面分步实现基于nginx的tomcat负载均衡和集群配置

一，tomcat集群

    1，先下载msm及其依赖包

    http://memcached-session-manager.googlecode.com/files/memcached-session-manager-1.3.0.jar

    http://memcached-session-manager.googlecode.com/files/msm-javolution-serializer-jodatime-1.3.0.jar

http://memcached-session-manager.googlecode.com/files/msm-javolution-serializer-cglib-1.3.0.jar

http://spymemcached.googlecode.com/files/memcached-2.4.2.jar

 

http://memcached-session-manager.googlecode.com/files/javolution-5.4.3.1.jar

2，将这5个包放到$TOMCAT_HOME/lib目录下

 

3，修改$TOMCAT_HOME/conf/server.xml

<Context docBase="E:/java_codes/TestSession/WebContent" path="" reloadable="true" >
<Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
    memcachedNodes="n1:localhost:11211"
    requestUriIgnorePattern=".*.(png|gif|jpg|css|js)$"
    sessionBackupAsync="false"
    sessionBackupTimeout="100"
    transcoderFactoryClass="de.javakaffee.web.msm.serializer.javolution.JavolutionTranscoderFactory"
    copyCollectionsForSerialization="false"
    />
</Context>

<Context docBase="E:/java_codes/TestSession/WebContent" path="" reloadable="true" >
<Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
    memcachedNodes="n1:localhost:11211"
    requestUriIgnorePattern=".*.(png|gif|jpg|css|js)$"
    sessionBackupAsync="false"
    sessionBackupTimeout="100"
    transcoderFactoryClass="de.javakaffee.web.msm.serializer.javolution.JavolutionTranscoderFactory"
    copyCollectionsForSerialization="false"
    />
</Context>

 这里的memcachedNodes是填写memcached节点,多个节点时可以以空隔分开，如:

 n1:localhost:11211 n2:localhost:11212

 

 sessionBackupTimeout的单位为分钟

 E:/java_codes/TestSession/WebContent 替换成你的WEB目录

  修改后重启两个TOMCAT即可,这个时候已经解决SESSION的共享问题.

 

二，配置nginx实现负载均衡

   以我的nginx.conf为例

#user  nobody;
worker_processes  1;

error_log  logs/error.log;

events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    sendfile        on;
    keepalive_timeout  65;

    #gzip  on;
    upstream  www.docyeah.com   {
              server   192.168.1.11:8080;
              server   192.168.1.101:8080;
    }
    server {
        listen       80;
        server_name  www.docyeah.com;
        charset utf-8;
        location / {
            root   html;
            index  index.html index.htm;
            proxy_pass        http://www.docyeah.com;
            proxy_set_header  X-Real-IP  $remote_addr;
            client_max_body_size  100m;
        }


        location ~ ^/(WEB-INF)/ {
        deny all;
        }

        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

    }
}

#user  nobody;
worker_processes  1;

error_log  logs/error.log;

events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    sendfile        on;
    keepalive_timeout  65;

    #gzip  on;
    upstream  www.docyeah.com   {
              server   192.168.1.11:8080;
              server   192.168.1.101:8080;
    }
    server {
        listen       80;
        server_name  www.docyeah.com;
        charset utf-8;
        location / {
            root   html;
            index  index.html index.htm;
            proxy_pass        http://www.docyeah.com;
            proxy_set_header  X-Real-IP  $remote_addr;
            client_max_body_size  100m;
        }


        location ~ ^/(WEB-INF)/ { 
	    deny all; 
        } 

        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

    }
}

将www.docyeah.com替换成你的域名

192.168.1.11和192.168.1.101替换成你服务器的IP

OK，已经完成。启动nginx即可。

 

这是我采用的负载均衡及集群方案，希望大家拍砖.

ps:javaeye的编辑器有问题，代码里加颜色后居然变乱了