Yarkon Server requires a license key:
Once your new server is up and running, go to the Administration page, the Database tab, and click the Restore button. Choose the backup file you created before. If any migration is required, it would be handled automatically.
Lastly, you want to put the new server in route, and discard the old one. Depending on your network settings, update the DNS to point to the new server. Once you confirm all functionality is in place, you can safely terminate the old instance.