illumos

illumos is a free, open source operating system (OS).

illumos consists of a kernel, network stack, file system, system libraries, device drivers and utility software for system management.

Distinguishing features of illumos include:

• ZFS combined file system and logical volume manager for large storage volumes
• DTrace dynamic tracking framework for troubleshooting kernel and application problems
• Kernel-based virtual machine (KVM) supporting native hardware virtualization on processors with hardware virtualization extensions
• Zones, a low-overhead OS virtualization technology
• Crossbow networking virtualization technology

illumos was developed as a fork of Unix-based OpenSolaris, the open source community-built derivative of the Solaris OS. The project launched in 2010. Major contributors include technologists from Delphix, Joyent, Nexenta Systems, and Pluribus Networks.