After upgrading Cacti from RPMForge cacti images/etc are linked to / rather than the /cacti/ directory.

To resolve this you will need to edit the "/var/www/cacti/include/config.php" file will your chosen text editor and add in the following config option.

$url_path = "/cacti/";

After this has been saved you will be able to visit your Cacti installation and the links will function correctly.