DTC (Domain Technologie Control)
Domain Technologie Control (DTC) is a control panel aiming at commercial hosting. Using a web GUI for the administration and accounting all hosting services, DTC can delegate the task of creating subdomains, email, ssh, database, mailing lists, and FTP accounts to users for the domain names they own. DTC manages a MySQL database containing all the hosting informations, and configure your server's services and apllication for doing virtual hosting (DTC is compabible with a huge list of applications). It also connects to dtc-xen to manage and monitor the usage of Virtual Private Servers (VPS), it does the billing in general (including billing of dedicated servers), has integrated support tickets and more. DTC is also the only control panel that made it to the distributions (it is included in FreeBSD and Debian as of writing), as it uses only packages available in them, surpassing even commercial solutions. In short, DTC is THE hosting software you need for everyday server administration if you do web, dns, ftp or mail hosting.
