Why Apache mod_rewrite rewrites twice my URL?

Question

I need to rewrite /admin/page/create URL to /backend/www/index.php/page/create, so I use the next Apache rewrite rule and conditions:

RewriteCond %{REQUEST_URI} !-f
RewriteCond %{REQUEST_URI} !-d
RewriteCond %{REQUEST_URI} !backend\/www

RewriteRule admin\/(.*)$ backend/www/index.php/$1 [NS,L]

However, examining the rewrite log, I see Apache rewrites correctly the URL, but at the end it performs an additional rewrite considering /page/create URL, which doesn't match any condition, so it fails and I receive the "No input file specified." error.

How can I prevent Apache to perform that additional rewrite? I used NS flag and RewriteCond %{IS_SUBREQ} f condition and it also performs the subrequest.

Thank you!

80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (2) init rewrite engine with requested uri /admin/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (1) pass through /admin/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] add path info postfix: /home/daniloaz/dev.daniloaz.com/httpdocs/admin -> /home/daniloaz/dev.daniloaz.com/httpdocs/admin/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] strip per-dir prefix: /home/daniloaz/dev.daniloaz.com/httpdocs/admin/page/create -> admin/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] applying pattern 'admin\/(.*)$' to uri 'admin/page/create'
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (4) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] RewriteCond: input='/admin/page/create' pattern='!-f' => matched
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (4) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] RewriteCond: input='/admin/page/create' pattern='!-d' => matched
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (4) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] RewriteCond: input='/admin/page/create' pattern='!backend\/www' => matched
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (4) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] RewriteCond: input='/admin/page/create' pattern='((admin\/(.*)$)|(admin$))' => matched
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (4) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] RewriteCond: input='false' pattern='f' => matched
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (2) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] rewrite 'admin/page/create' -> 'backend/www/index.php/page/create'
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] add per-dir prefix: backend/www/index.php/page/create -> /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (2) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] strip document_root prefix: /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php/page/create -> /backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a35d60/initial] (1) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] internal redirect with /backend/www/index.php/page/create [INTERNAL REDIRECT]
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (2) init rewrite engine with requested uri /backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (1) pass through /backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] add path info postfix: /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php -> /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] strip per-dir prefix: /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php/page/create -> backend/www/index.php/page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (3) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] applying pattern 'admin\/(.*)$' to uri 'backend/www/index.php/page/create'
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a472f0/initial/redir#1] (1) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] pass through /home/daniloaz/dev.daniloaz.com/httpdocs/backend/www/index.php
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a4ce60/subreq] (2) init rewrite engine with requested uri /page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a4ce60/subreq] (1) pass through /page/create
80.29.4.44 - - [13/Jun/2013:21:40:54 +0200] [dev.daniloaz.com/sid#7f65e59b6a78][rid#7f65e5a4ce60/subreq] (1) [perdir /home/daniloaz/dev.daniloaz.com/httpdocs/] pass through /home/daniloaz/dev.daniloaz.com/httpdocs/page

Answer 1

Well, I finally solved this issue using a workaround. First I tried these solutions, but subrequests were performed again and again and rewriting failed as before.

With mod_rewrite, there are small differences if you put a rule in .htaccess or in global configuration (httpd.conf, Virtualhost configuration, etc.). Subrequests are one of that differences. Just place the same rule I mentioned above in Virtualhost config file instead of .htaccess and subqueries stop and everything starts working like a charm.

I recommend this useful post to fully understand the internals of mod_rewrite before trying to solve any related to it issue: http://net.tutsplus.com/tutorials/other/a-deeper-look-at-mod_rewrite-for-apache/