Multisites placed inside sub site folder?
Good question. It is possible to run drupal multisites as a subdirectory even if your Drupal installation is in a subdirectory itself.


  Side note: the /sites/ directory in your examples is not necessary.


Given that your main Drupal install is accesible at domain.com/drupal the solution is to use symlinks to tell your webserver that the document root for domain.com/drupal/multisite is the same as your main drupal install (domain.com/drupal).


The first step is to create a directory for the multisite. The syntax is a little different for subdirectory multisites: domain.com.multisite. So, inside your /sites directory, you will have something like this:


-|/sites
--|----/all
--|----/default
--|----/domains.com.multisite

Place a copy of default.settings.php in domains.com.multisite and rename it to settings.php.
Then create the symlink described above by running the following command from your main website's docroot (not Drupal's docroot, the main website's docroot - usually public_html or something similar):


ln -s [drupal-directory-name] [multisite-directory-name]



Or, using the names in our example above:

ln -s drupal multisite


See Drupal's multisite documentation for more information.