HD-Canon plugin for Joomla 2.5

Give your Joomla 2.5 site canonical URLs to avoid duplicate content issues.




Download for Joomla 2.5


what is this? | what does that mean? | death? | what to do after installing? | examples | help


What is this?

HD-Canon is a simple plugin that ensures your site's URLs are canonical.



What does that mean?

Canonical URLs are URLs that consistantly share the same prefix.

Most web hosts enable your website to be accessed with both the www and the non-www. prefix. Unfortunately search engines would consider http://yoursite.com and http://www.yoursite.com as two entirely seperate sites, potentially leading to duplicate content issues and in some cases death.




Worse. Google doesn't want two sites with the same content to appear next to each other in their search results so your site could be considered spam.

This plugin simply lets you decide if your site should be www or non-www dominant, and if you try to access the lesser URL you will be redirected to the canonical URL.



What to do after installing?

Install the zip file via the administration install manager as per any other plugin. Once it has installed go to the plugin manager and select HD-Canon. Enable the plugin and enter your chosen prefix.


You only need to enter the domain name (with or without www.), do not enter http:// before the domain or a trailing slash ( / ) after the domain as this will cause issues on your live site.


Similarly if your Joomla installation isn't in the root folder (eg. http://www.yoursite.com/testsite ) then do not enter the folder extension or your site will forward to http://www.yoursite.com/testsite/testsite (in this case just enter www.yoursite.com ).



Here is a correct entry to ensure http://www.yoursite.com is the canonical URL.




Here are a few incorrect entries that will lead to problems...







Help! I'm locked out!

If you have added an incorrect canonical URL and the site has "locked you out" of the correct URL (including your admin access), use the following instructions to regain control...


  1. Using an FTP manager locate this file... plugins > system > canon > canon.php
  2. Rename the canon.php file to something else (eg. "old-canon.php")
  3. You should now be able to gain access to the site. Once you have re-entered the canonical URL, renaming the file back to canon.php will resolve your issue.
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