Nginx global configuration files to ease the configuration of wordpress multisite installations under nginx/php-fpm. Simply import these configurations in your specific configuration

restrictions.conf

# Global restrictions configuration file.
# Designed to be included in any server {} block.</p>
location = /favicon.ico {
	log_not_found off;
	access_log off;
}

location = /robots.txt {
	allow all;
	log_not_found off;
	access_log off;
}

# Deny all attempts to access hidden files such as .htaccess, .htpasswd, .DS_Store (Mac).
location ~ /\. {
	deny all;
	access_log off;
	log_not_found off;
}

wordpress-ms-subdir.conf

# WordPress multisite subdirectory rules.
# Designed to be included in any server {} block.

# This order might seem weird - this is attempted to match last if rules below fail.
# http://wiki.nginx.org/HttpCoreModule
location / {
	try_files $uri $uri/ /index.php?$args;
}

# Add trailing slash to */wp-admin requests.
rewrite /wp-admin$ $scheme://$host$uri/ permanent;

# Directives to send expires headers and turn off 404 error logging.
location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
	expires 24h;
	log_not_found off;
}

# Pass uploaded files to wp-includes/ms-files.php.
rewrite /files/$ /index.php last;

# For multisite:  Use a caching plugin/script that creates symlinks to the correct subdirectory structure to get some performance gains.
set $cachetest "$document_root/wp-content/cache/ms-filemap/${host}${uri}";
if ($uri ~ /$) {
	set $cachetest "";
}
if (-f $cachetest) {
	# Rewrites the URI and stops rewrite processing so it doesn't start over and attempt to pass it to the next rule.
	rewrite ^ /wp-content/cache/ms-filemap/${host}${uri} break;
}

if ($uri !~ wp-content/plugins) {
	rewrite /files/(.+)$ /wp-includes/ms-files.php?file=$1 last;
}

# Uncomment one of the lines below for the appropriate caching plugin (if used).
# include global/wordpress-ms-subdir-wp-super-cache.conf;
# include global/wordpress-ms-subdir-w3-total-cache.conf;

# Rewrite multisite '.../wp-.*' and '.../*.php'.
if (!-e $request_filename) {
	rewrite ^/[_0-9a-zA-Z-]+(/wp-.*) $1 last;
	rewrite ^/[_0-9a-zA-Z-]+.*(/wp-admin/.*\.php)$ $1 last;
	rewrite ^/[_0-9a-zA-Z-]+(/.*\.php)$ $1 last;
}

# Pass all .php files onto a php-fpm/php-fcgi server.
location ~ \.php$ {
	# Zero-day exploit defense.
	# http://forum.nginx.org/read.php?2,88845,page=3
	# Won't work properly (404 error) if the file is not stored on this server, which is entirely possible with php-fpm/php-fcgi.
	# Comment the 'try_files' line out if you set up php-fpm/php-fcgi on another machine.  And then cross your fingers that you won't get hacked.
	try_files $uri =404;

	fastcgi_split_path_info ^(.+\.php)(/.+)$;
	include fastcgi_params;
	fastcgi_index index.php;
	fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
#	fastcgi_intercept_errors on;
	fastcgi_pass php;
}