Magento – Second website on subfolder doesn’t work: how to debug

It's very easy to serve multiple domains/paths based on URLs. As mentioned, the easiest setup (configuration-only) is possible when the unique core/store codes can be used in the path as subfolders. This requires one of the following:

1. Visitors are linked to the correct subfolder path initially
2. Visitors are served a landing page from which they select their store and receive a cookie
3. Some mechanism is used to set the run type and run code prior to PHP handling the response

Regarding #3: since 1.4 Magento, made it possible to allow the Web server to determine the running context (website or store) as well as the particular code which should be used. From index.php:

/* Store or website code */
$mageRunCode = isset($_SERVER['MAGE_RUN_CODE']) ? $_SERVER['MAGE_RUN_CODE'] : '';

/* Run store or run website */
$mageRunType = isset($_SERVER['MAGE_RUN_TYPE']) ? $_SERVER['MAGE_RUN_TYPE'] : 'store';

Mage::run($mageRunCode, $mageRunType);

Whereas environment variables are used to initialize the application, it's possible to influence the system prior to PHP even spinning up. With Apache and mod_rewrite this can be done for subfolders with a bit of trickery:

RewriteCond %{REQUEST_URI} ^/de/$
RewriteRule .* - [E=MAGE_RUN_CODE:deutsch]
RewriteCond %{ENV:REDIRECT_MAGE_RUN_CODE} (.+)
RewriteRule .* - [E=MAGE_RUN_CODE:%1]

Apache is twitchy with environment variables and subfolders, as demonstrated by this excellent SO answer. The initial two lines result in $_SERVER["REDIRECT_MAGE_RUN_CODE"] = 'deutsch'; while the latter two lines provide the needed $_SERVER["MAGE_RUN_CODE"] = 'deutsch';. There are numerous other tricks, but the above has bitten me before.

The end goal should be initial detection as much as is reasonable (geoip + multi-language concerns) while getting the user to set the store cookie which can be used to bypass/step through the logic in subsequent requests.

The problem is that just copying the index.php file will not do the trick, because all the app/ folder etc is missing.

To get around this, in your index.php you need to set the MAGENTO_ROOT to be one folder up:

define('MAGENTO_ROOT', getcwd() . '/..');

Then it should work.

However, you also want to make sure that your skin etc is loaded from the parent folder, so in your Magento backend, you will need to enter http://mydomain.at/ instead of http://mydomain.at/en/ for skin, images etc in the URL management.

Hope this helps!