配置文件改成这样

server {
    listen 80; 
 server_name sub.domain.com; 
 set $root_path '/srv/www/default'; 
 root $root_path; 
  
 index index.php index.html index.htm; 
  
 try_files $uri $uri/ @rewrite; 
  
 location @rewrite { 
  rewrite ^/(.*)$ /index.php?_url=/$1; 
 } 
  
 location ~ \.php { 
  
  fastcgi_pass 127.0.0.1:9000; 
  fastcgi_index /index.php; 
  
  fastcgi_split_path_info    ^(.+\.php)(/.+)$; 
  fastcgi_param PATH_INFO    $fastcgi_path_info; 
  fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info; 
  fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; 
  include            fastcgi_params;
 } 
  
 location ~* ^/(css|img|js|flv|swf|download)/(.+)$ { 
  root $root_path; 
 } 
  
 location ~ /\.ht { 
  deny all; 
 } 
  }

在CentOS7.1+Nginx1.8.0+Laravel5.0测试通过