FAI is a non-interactive system to install, customize and manage Linux systems and software configurations on computers as well as virtual machines and chroot environments, from small networks to large-scale infrastructures like clusters and cloud environments.

Castle is a key-value store responsible for redundancy, caching, indexing and disk layout management. Acunu uses it to store all user data as well as statistics captured and displayed by the Control Center.
Castle is not cluster aware and thus it doesn’t participate in distributing data in a cluster. However, Castle interfaces are designed with distributed databases in mind, featuring timestamps and automated discarding of old, deleted data.

The Yocto Project™ is an open source collaboration project that provides templates, tools and methods to help you create custom Linux-based systems for embedded products regardless of the hardware architecture.

ConMan is a serial console management program designed to support a large number of console devices and simultaneous users.

Ganeti is a cluster virtual server management software tool built on top of existing virtualization technologies such as Xen or KVM and other Open Source software.

Froxlor: The server administration software for your needs.
Developed by experienced server administrators this open source (GPL) panel simplifies the effort of managing your hosting platform.