1. Create an A record and click on the double arrows icon.
2. A page will pop-up with the Dynamic URL of that particular A record and some example scripts you can use with crontab.
3. Save one of the scripts with your favourite text editor. We will use the Perl script in this example.
4. Open Terminal (if needed) and type the command $ crontab -e. It will open your user's crontab. If it
asks you to choose between several text editors choose one and hit Enter. The crontab will open and
you will be able to add a cron job for that script. Save the crontab with ctrl+x, they press the y button
on your keyboard and then Enter. The bellow entry will execute the script every first minute of every
hour.
How to set up Dynamic DNS for *NIX - Step by Step: