Howtoforge shows how web site administrators can mirror their web site to a backup server that can take over should the main server fail. Using a tool called rsync and a cron job, the main server is continually queried for the existence of new or updated data. If such data exists, it is copied to the backup server so that it becomes an exact mirror of the main server. By using this method, a minimal burden is placed on the main server and the backup remains up-to-date and ready to stand in as the primary should the main server go off-line.