To make the links other posts more domain name independent, it would be nice to have internal links.

By default Drupal does not have this feature, but it is possible by using PathFilter.

PathFilter

PathFilter translate a relative internal path to a full URL. This module integrates with the Drupal HTML Filter.

The project page of PathFilter is here: http://drupal.org/project/pathfilter

Download the latest version and put the module into your Drupal modules directory (/sites/all/modules).

The activate and configure the module, do the following steps:

  1. Activate the PathFilter module in menu: Home»Administer»Site building»Modules
  2. Go to menu: Home»Administer»Site configuration»Input formats
  3. Click on configure at the HTML Filter you use for your posts (normally Filtered HTML)
  4. Select in the Filter group the item: Internal path filter
  5. Clear your cache in menu Home»Administer»Site configuration»Performance and click on Clear cached data

I tested this with CKEditor, but I think the base is the same for other editors.

  1. Open a new post and check, under the Input format, for the HTML filter selection. This has to be the same HTML filter as you configured above.
  2. Now insert an link with Linktype: **URL **and Protocol:
  3. Now full in the URL for example: internal:node/189 or internal:content/changelog-site

Attention! Path Filter and a multi-domain Drupal installation is not recommendable. Sometimes an internal link will be redirected to an another domain. This results in broken links en that is not nice for the visitors and not good for the SEO ranking.