Question

I am trying to redirect all traffic into a subdomain.

http://www.example.com, example.com, sub.othersite.com
all rewrite to sub.othersite.com

It works great. Now I need to exclude a single URL from redirecting to the subdomain

So if http://www.example.com/THE/URI comes in, I want mod rewrite to ignore the subdomain rewrite and send it to the main domain.

Seems simple enough but I can’t get it to work because I have an additional rewrite that makes sure all the domains (there are a couple parked ones as well) funnel into a single domain to deliver the content.

I have a few other rewrite conditions. They are all listed here. If someone could point me in the right direction – I need to basically do this:

IF incoming request is for /THE/URI
then go to http://www.example.com/THE/URI
otherwise
rewrite to sub.othersite.com

<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteBase /

  # ignore system folder
  RewriteCond %{REQUEST_URI} ^system.*
  RewriteCond $1 !^(client/*)   
  RewriteRule ^(.*)$ /index.php?/$1 [L]

  #Checks to see if the user is attempting to access a valid file,
  #such as an image or css document, if this isn't true it sends the
  #request to index.php
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteCond $1 !^(index\.php|images|robots\.txt|css)
  RewriteRule ^(.*)$ index.php?/$1 [L] 

  # if it is the SPECIAL URI redirect and EXIT
  RewriteCond $1 !^(/THE/URI)   
  RewriteCond %{HTTP_HOST} !^www.example.com$
  RewriteRule ^(.*)$ http://www.example.com/THE/URI [L]

  #catch all other traffic        
  RewriteCond %{HTTP_HOST} !^example.anothersite.com$
  RewriteRule ^(.*)$ http://example.anothersite.us/$1 


</IfModule> 

Answer 1

Solved.
The answer was simple. I just needed to exclude both the URI and the QUERY_STRING from the final rewrite, since the top half of the rewrite appends the URL with a query string.

In order for my application to work, I still needed the initial rewrite (take any URI and internally map it to index.php?URI)

Final code:

<IfModule mod_rewrite.c>
        RewriteEngine On
        RewriteBase /

        #Removes access to the system folder by users.
        RewriteCond %{REQUEST_URI} ^system.*
        RewriteCond $1 !^(client/*)   
        RewriteRule ^(.*)$ /index.php?/$1 [L]

                # our URL is prepped now - query string appended, so let's redirect it
                # ONLY if it's not the ONE URL we need to keep

        RewriteCond %{REQUEST_URI} !^/THE/URI   
        RewriteCond %{QUERY_STRING} !^/THE/URI
        RewriteCond %{HTTP_HOST} !^sub.example.com$
        RewriteRule ^(.*)$ http://sub.example.com/$1  [R=302]
</IfModule>