nginx.conf to rewrite of example.com/sites/medicine to medicine.example.com

gistfile1.nginxconf

user www-data;
worker_processes 4;
pid /var/run/nginx.pid;

events {
#  worker_connections 768;
 worker_connections 7680;
# multi_accept on;
}

error_log /var/log/nginx/error.log;

http{
	

	##
	# Basic Settings
	##

	sendfile on;
	tcp_nopush on;
	tcp_nodelay on;
	keepalive_timeout 65;
	types_hash_max_size 2048;
	# server_tokens off;

	# server_names_hash_bucket_size 64;
	# server_name_in_redirect off;


	include /etc/nginx/mime.types;
	default_type application/octet-stream;

	##
	# Logging Settings
	##

	access_log /var/log/nginx/access.log;
	error_log /var/log/nginx/error.log;


	##
	# Virtual Host Configs
	##

	include /etc/nginx/conf.d/*.conf;
	include /etc/nginx/sites-enabled/*;


#server {
#  listen 80;
#  listen 443 ssl spdy;
#  server_name medicine.example.com;
#  return 301  https://example.com/sites/medicine$request_uri;
#}


#    location / {
#        resolver            8.8.8.8;
#        rewrite             ^([^.]*[^/])$ $1/ permanent;
#        proxy_pass_header   Set-Cookie;
#        proxy_pass          https://example.com/sites/physics$request_uri;
#    }
#}

#server {
 # server_name user.cooking.com;
 # include sites-available/server.conf;
 # fastcgi_param  SCRIPT_FILENAME  $document_root/index.php/user/$args;
 # include sites-available/php.conf;
#}

server {
#   listen   80;
    listen   443 ssl spdy;
    ssl    on;
    ssl_certificate    xxxxxxx.xxx;
    ssl_certificate_key    xxxxxxxx.xxx;

#   server_name example.com;
    server_name example.com physics.example.com medicine.example.com;
    root   /var/www;
#   index index.html index.php index.htm;
    access_log /var/log/nginx/access.log;
    error_log /var/log/nginx/error.log;

    if ($host = "physics.example.com") {
        rewrite . /sites/physics$request_uri;
    }

#   if ($host ~* ^www\.([a-z0-9]*)\.(example\.com) )
#   {
#     set $storename $1;
#     set $host_without_www $2;
#     rewrite ^/(.*)$ $scheme://$storename.$host_without_www/ permanent;
#   }

#   if ($host ~* ^([a-z0-9]+)\.(example\.com))
#   {
#      set $storename $1;
#      set $host_without_www $2;
#      rewrite ^/$ /index.php/tags/index/ last;
#      rewrite ^/(.+)$ /index.php/$1 last;
#    }


  # canonicalize codeigniter url end points
  # if your default controller is something other than "welcome" you should change the following
#   if ($request_uri ~* ^(/mall(/index)?|/index(.php)?)/?$){
#       rewrite ^(.*)$ / permanent;
#       rewrite ^/(.*) http://example.info/$1 permanent;
#   }

    # removes trailing "index" from all controllers
    if ($request_uri ~* index/?$){
        rewrite ^/(.*)/index/?$ /$1 permanent;
    }

    # removes trailing slashes (prevents SEO duplicate content issues)
    if (!-d $request_filename){
        rewrite ^/(.+)/$ /$1 permanent;
    }

    # removes access to "system" folder, also allows a "System.php" controller
    if ($request_uri ~* ^/system){
        rewrite ^/(.*)$ /index.php?/$1 last;
        break;
    }

    # unless the request is for a valid file (image, js, css, etc.), send to bootstrap
    if (!-e $request_filename){
        rewrite ^/(.*)$ /index.php?/$1 last;
        break;
    }
 
    # catch all
    error_page 404 /index.php;

    location / {
      #try_files $uri $uri/ /index.php;
       index index.php   index.html; 
    }
  
    # use fastcgi for all php files
    location ~ \.php$
    {
        fastcgi_pass 127.0.0.1:9000;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME /var/www$fastcgi_script_name;
        include /etc/nginx/fastcgi_params;
    }

    # deny access to apache .htaccess files
    location ~ /\.ht {
        deny all;
    }


 } #end server

  proxy_buffer_size   128k;
  proxy_buffers   4 256k;
  proxy_busy_buffers_size   256k;
  fastcgi_buffers 16 16k;
  fastcgi_buffer_size 32k;

} #end http