# The Unix Systems Still Alive in 2026: HP-UX Winds Down, z/OS and OpenVMS Hold On

- **Published on:** 2026-09-15
- **Category:** News
- **Original page:** https://linuxgratis.com/en/articles/unix-systems-still-alive-2026

HP-UX lost standard support in December 2025. Meanwhile z/OS, IBM i, AIX and an OpenVMS ported to x86 remain in production, and the community keeps Solaris's legacy running through illumos.

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When someone says "Unix" today they usually mean Linux or macOS. But the actual commercial Unix systems, the ones that ruled data centres in the nineties, have not entirely disappeared: some still get new versions and others are switching off right now. We added the missing ones to the catalogue, and the review draws an interesting map.

## HP-UX: that's it

[HP-UX](/en/hp-ux) is the one in the worst shape. Its last version, 11i v3, shipped in **February 2007** and HPE kept updating it for eighteen years, through the May 2025 refresh. Standard support ended on **31 December 2025**. Extended support runs to 2028 for those who pay, but that is not the same thing: it is palliative care for migrations, not a platform with a future.

Its problem was not the system but the processor. HP-UX tied itself to Itanium, and Itanium died.

## The ones still making money

[IBM z/OS](/en/zos) is the opposite case. It descends from MVS in 1974 and still moves a huge share of the planet's banking transactions. Version 3.2 arrived on **30 September 2025** and keeps compatibility with programs written half a century ago, which is exactly what a bank wants to hear. It also carries a certified Unix subsystem, so yes, it counts.

[IBM i](/en/ibm-i) is the direct heir of the AS/400's OS/400, today on Power servers. Its oddest trait seen from Linux: the Db2 database is not a program you install, it is built into the operating system. It still runs decades-old RPG and COBOL applications without recompiling.

[AIX](/en/ibm-aix), IBM's third, sits at 7.3 on that same Power hardware.

## OpenVMS: back from the dead

[OpenVMS](/en/openvms) deserves its own chapter because, strictly speaking, it is not even Unix. It was born in 1977 at Digital, from a different lineage and with different ideas: clustering from day one, file versioning in the system itself and a reputation for stability that has produced legends about machines running for years without a reboot.

Just when it looked doomed to die alongside Alpha and Itanium hardware, VMS Software Inc. bought the rights and **ported it to x86-64**. V9.2-3 is from November 2024 and still receives patches. A system from 1977 running today on an ordinary Intel server is not an everyday sight.

## Solaris's legacy

[Oracle Solaris](/en/oracle-solaris) continues, but the interesting part is elsewhere. When Oracle closed the OpenSolaris source in 2010, the community forked the last published code and carried on alone. That is [illumos](/en/illumos): not a distribution you install, but the shared base that preserves ZFS, DTrace and zones.

Three systems grow out of it, and all three now have their own entry:

- [OpenIndiana](/en/openindiana) is the most direct continuation of OpenSolaris as a desktop and server system, with Hipster snapshots every few months.
- [OmniOS](/en/omnios) does its own thing: servers, minimal, and a serious release calendar — stable every six months with a year of support, LTS every two years with three. It is one of the few small projects that publishes end-of-support dates years ahead and sticks to them.
- [SmartOS](/en/smartos) is the strangest: it boots from memory, without installing to disk, and is designed as a hypervisor. It combines zones, KVM and bhyve. It came out of Joyent and MNX maintains it today, with a fresh image every two weeks.

## What the review teaches

That systems rarely die from being bad. HP-UX is winding down because it bet on a processor that vanished. Solaris lost momentum when Oracle closed the source, and the free side survived in the hands of far fewer people. z/OS and IBM i carry on because migrating what runs on top would cost more than keeping them.

And OpenVMS holds on because somebody decided it was worth porting. You will find each one's dates on its entry, and the three illumos systems update themselves from their official sources.