All of our servers use Debian GNU/Linux as an operating system.

Some servers are virtual machines provided by Hetzner, we do not know which virtualization is used by Hetzner, chances are, that it is a commercial version of one of the prominent virtualization solutions VMware, OpenVZ or Xen, which have been developed originally as Open Source projects.

Typically we use the ext4 and the XFS file systems. The former for the system disk partitions, the latter for homedirectories and the disk space used for webhosting.

To bootstrap the operating system, GNU GRUB comes into play.