网站的目录结构为：

tree /home/wwwroot/exehack.net

/home/wwwroot/exehack.net
├── bbs
│ └── index.html
└── www
└── index.html
2 directories, 2 files

/home/wwwroot/exehack.net为nginx的安装目录下默认的存放源代码的路径。
bbs为论坛程序源代码路径；www为主页程序源代码路径；把相应程序放入上面的路径通过；http://www.exehack.net 访问的就是主页http://bbs.exehack.net 访问的就是论坛，其它二级域名类推。

有2种方法，推荐方法一

server {
listen 80;
server_name ~^(?<subdomain>.+).exehack.net$;
access_log /data/wwwlogs/exehack.net_nginx.log combined;
index index.html index.htm index.php;
root /home/wwwroot/linuxeye/$subdomain/;
location ~ .php$ {
  fastcgi_pass unix:/dev/shm/php-cgi.sock;
  fastcgi_index index.php;
  fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
  include fastcgi_params;
  }
location ~ .*\.(gif|jpg|jpeg|png|bmp|swf|flv|ico)$ {
  expires 30d;
  }
location ~ .*\.(js|css)?$ {
  expires 7d;
  }
}

方法二、

server {
listen 80;
server_name *.exehack.net;
access_log /home/wwwlogs/exehack.net_nginx.log combined;
index index.html index.htm index.php;
if ($host ~* ^([^\.]+)\.([^\.]+\.[^\.]+)$) {
  set $subdomain $1;
  set $domain $2;
}
location / {
  root /home/wwwroot/exehack.net/$subdomain/;
  index index.php index.html index.htm;
}
location ~ .php$ {
  fastcgi_pass unix:/dev/shm/php-cgi.sock;
  fastcgi_index index.php;
  fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
  include fastcgi_params;
  }
location ~ .*\.(gif|jpg|jpeg|png|bmp|swf|flv|ico)$ {
  expires 30d;
  }
location ~ .*\.(js|css)?$ {
  expires 7d;
  }
}

nginx将泛解析的匹配域名绑定到子目录的配置方法如下

server {
     listen        80;
     server_name   domain.com    *.domain.com;

    if ($host ~* ^([^\.]+)\.([^\.]+\.[^\.]+)$) {
         set $subdomain $1;
         set $domain $2;
     }

    location / {
         root    /home/wwwroot/$domain/$subdomain/;
         index   index.php index.html index.htm;
         #include /home/wwwroot/$domain/$subdomain/.ngx.htaccess;
     }

    error_page   500 502 503 504  /50x.html;

    location = /50x.html {
         root   html;
     }

    location ~ \.php$ {
         root           /home/wwwroot/$domain/$subdomain/;
         fastcgi_pass   127.0.0.1:9100;
         fastcgi_index  index.php;
         fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
         include        fastcgi_params;
     }
 }