OmniOS

Free plan LinuxSelf-hosted

What OmniOS is

OmniOS is a free, open-source server operating system based on illumos. It runs on x86-64 hardware and supports physical servers and virtual machines, including AWS EC2 cloud images. Its native ZFS filesystem combines volume management and filesystem functions with data-integrity protection, and can share storage through iSCSI, CIFS, and NFS. Containers can run lightweight OmniOS or Linux virtual machines with resource controls. Hardware virtualization is provided through bhyve and KVM, including Windows and FreeBSD guests. Crossbow virtual interfaces and switches provide virtualized networking and resource allocation for services, while DTrace traces activity across the software stack for troubleshooting. The Kayak framework supports network deployment and, according to the project, can build one virtual machine in less than two minutes. OmniOS uses the IPS package manager and digitally signed updates. Stable releases receive one year of support; every fourth stable release is an LTS release with three years.

Who it suits

OmniOS suits organizations running x86-64 servers or virtual machines that need ZFS storage, containers, guest virtualization, and virtualized networking. It also fits teams that want an open-source operating system with defined stable and LTS support periods.

What it does well

Free open-source server operating system
ZFS includes integrity protection and storage sharing
Supports bhyve and KVM guest virtualization
DTrace provides software-stack troubleshooting traces
Digitally signed package updates

What to know first

Releases support x86-64 only
Stable releases receive one year of support
Support package costs $500 a year
Support reaction time is best-effort, not guaranteed

Plans

Plan	Billed and limits	Price
OmniOS Community Edition	Open-source server OS · x86-64 only	Free
OmniOS Support Package	12 months; per server · Best-effort 4-hour reaction time · no guaranteed problem resolutions · weekly security updates as necessary · direct developer access for second-level support	$500 a year

As omnios.org lists them, read 8 Oct 2026. The maker's own page has the final word.

Verdict

OmniOS combines illumos-based server operation with ZFS, containers, virtualization, networking, and tracing tools. The free edition is limited to x86-64, while longer support and developer access require the paid support package.

Facts from OmniOS's own pages

Commercial support: The support package includes weekly security updates as necessary, LTS releases with one year migration overlap, and direct developer access for second-level support. · omnios.org, 8 Oct 2026
Containers: OmniOS can run lightweight OmniOS or Linux virtual machines in containers with resource controls. · omnios.org, 8 Oct 2026
Hardware virtualization: The system provides hardware virtualization via bhyve and KVM, including for Windows and FreeBSD guests. · omnios.org, 8 Oct 2026
Headquarters: Olten, Switzerland · omnios.org, 28 Sept 2026
Installation: The Kayak installation framework supports network deployment and can build a single VM in less than two minutes, according to the project. · omnios.org, 8 Oct 2026
Maintainer: The OmniOS Community Edition Association is a Swiss association dedicated to continuing OmniOS support and releases. · omnios.org, 8 Oct 2026
Networking: Crossbow virtual interfaces and switches support virtualized networking and resource allocation for services. · omnios.org, 8 Oct 2026
Purpose: OmniOS is an open-source server operating system based on illumos. · omnios.org, 8 Oct 2026
Release architecture: All OmniOS releases are for x86-64 architecture only. · omnios.org, 8 Oct 2026
Release support: Stable releases are supported for one year, while every fourth stable release is an LTS release supported for three years. · omnios.org, 8 Oct 2026
Storage: Its native ZFS filesystem combines volume management and filesystem features with data-integrity protection, and supports sharing via iSCSI, CIFS, and NFS. · omnios.org, 8 Oct 2026
Support limitation: The support contract offers a best-effort reaction time of four hours on its Gitter support channel and does not guarantee problem resolution. · omnios.org, 8 Oct 2026
Tracing: DTrace provides dynamic tracing across the software stack for troubleshooting. · omnios.org, 8 Oct 2026
Updates: OmniOS provides digitally signed package updates; LTS releases receive updates for three years. · omnios.org, 8 Oct 2026

Where OmniOS stands on Freedom251

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