Fix Duplicate Content Problem in Typo3
Typo3 like many other CMS'es have a problem with url's. In Typo3 the RealUrl extension does a great job of allowing nice urls for pages which is great for seo, however the pages are still available from the "old" url (index.php?id=xxx). It is even worse for the home page of your website - it can be accessed by
- www.yourdomain.tld
- www.yourdomain.tld/index.php
- www.yourdomain.tld/index.php?id=
- www.yourdomain.tld/index.php?id=0
- www.yourdomain.tld/index.php?id=[actual page id
This is a problem if the search engines penalize you for duplicate content. There is, luckily, and easy fix for this. You can tell the search engines which page is the real page and subsequently which ones are copies that you know are there, but which should not be considered. The trick is to put a link tag, with a rel-attribute with the value of canonical and then put the "real" url in the href-attribute. This tells google (and friends) that the referenced page is the page that should be considered for indexing.
In typo3 there is a short snippet that can help you to do this automatically for all pages.
This creates the tag with the real url in the header of every page.
UPDATE: as Steffen points out in the comments below, this solution will only work if you have no plugins that append data to the url for their view. In these cases the Typo3 Extension Canonical is probably your best bet for a solution.