TrueNAS (formerly FreeNAS) is a family of Linux and FreeBSD based network-attached storage (NAS) operating systems developed by iXsystems. The operating systems include components released under a proprietary license, GPL and BSD licenses. TrueNAS can be installed for free on commodity x86-64 computers or TrueNAS Enterprise purchased as a turnkey appliance with support from iXsystems.
Built around the OpenZFS file system, TrueNAS provides a number of built-in file and block storage services as well as an OS-level virtualized app store (Linux containers and FreeBSD jails respectively) and virtual machine hypervisor to host additional services.