Nginx+Tomcat负载均衡

Nginx是一款轻量级的Web 服务器/反向代理服务器及电子邮件(IMAP/POP3)代理服务器,并在一个BSD-like 协议下发行。 其特点是占有内存少,并发能力强,事实上nginx的并发能力确实在同类型的网页伺服器中表现较好。

准备
nginx:nginx/Windows-1.10.1 http://nginx.org/en/download.html
tomcat:apache-tomcat-6.0.45

准备2个tomcat服务器分别命名为:

apache-tomcat-6.0.45-8090
apache-tomcat-6.0.45-8091

同时修改server.xml文件中的端口号,有三个端口号需要修改,防止端口冲突:

1.<Server port="8005" shutdown="SHUTDOWN">
2.<Connector port="8090" protocol="HTTP/1.1" ...
3.<Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />

修改tomcat默认首页:webapps/ROOT/index.html,用于识别当前进入的是哪个tomcat:

<td align="left" valign="top"><b>Apache Tomcat------8090</b></td>
<td align="left" valign="top"><b>Apache Tomcat------8091</b></td>

nginx.conf配置
修改conf/nginx.conf文件

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;


events {
    worker_connections  1024;
}


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;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;
	
    upstream suroot{
        server 127.0.0.1:8090 max_fails=2 fail_timeout=30s;
        server 127.0.0.1:8091 max_fails=2 fail_timeout=30s;
    }

    server {
        listen       80;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location / {
            root   html;
            index  index.html index.htm;
	    proxy_pass http://suroot/;   #请求转向suroot定义的服务器列表
	    #以下是一些反向代理的配置可删除.
            proxy_redirect off;
            proxy_set_header   Host $host;
            proxy_set_header   X-Real-IP $remote_addr;
            proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
            client_max_body_size   10m;#允许客户端请求的最大单文件字节数
            client_body_buffer_size   128k;#缓冲区代理缓冲用户端请求的最大字节数,
            proxy_connect_timeout   600;#nginx跟后端服务器连接超时时间(代理连接超时)
            proxy_send_timeout   600; #后端服务器数据回传时间(代理发送超时)
            proxy_read_timeout   600; #连接成功后,后端服务器响应时间(代理接收超时)
            proxy_buffer_size   8k; #设置代理服务器(nginx)保存用户头信息的缓冲区大小
            proxy_buffers   4 64k;#proxy_buffers缓冲区,网页平均在32k以下的话,这样设置
            proxy_busy_buffers_size   128k;#高负荷下缓冲大小(proxy_buffers*2)
            proxy_temp_file_write_size  128k;#设定缓存文件夹大小,大于这个值,将从upstream服务器传
        }

        #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   html;
        }

        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ \.php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ \.php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000;
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #    deny  all;
        #}
    }


    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl;
    #    server_name  localhost;

    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_cache    shared:SSL:1m;
    #    ssl_session_timeout  5m;

    #    ssl_ciphers  HIGH:!aNULL:!MD5;
    #    ssl_prefer_server_ciphers  on;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}

}

测试
1.tomcat/bin/startup.bat分别启动2个tomcat
2.启动nginx
执行nginx.exe或者使用命令:start nginx

常用命令:

start nginx           启动
nginx -s stop         停止服务
nginx -t              验证nginx.conf是否正确
nginx -s reload       改变了nginx配置信息并需要重新载入

因为nginx启动的端口是80,所以我们直接访问:http://localhost/

不停刷新页面,经测试Apache Tomcat——8090和Apache Tomcat——8091交替出现