The final version of HPE's own flavor of Unix, HP-UX 11i v3, is now out of support. It is the end of a line that started in 1982.

According to HPE's HP-UX support matrix, the end of life for the final version was the last day of last year:

The product status is now "Mature Software Product Support without Sustaining Engineering through at least 31-Dec-2028."

HPE's version numbers are complex, but the last release of HP-UX that we can find is HP-UX 11i v3 release 2505.11iv3, which was released on May 22, 2025, for HPE's Integrity servers – as The Register put it a decade ago, "Integrity servers means the Superdome ones running HP-UX with Intel's fading Itanium processors and NUMA."

At least one website misses it already. Last week, OSnews reported "HP-UX hits end-of-life today, and I'm sad." Some see this as a potential opportunity. For instance, SUSE used the news to offer an escape route, explaining "Why SUSE Linux is the Natural Heir."

HP-UX had a good run, after a long and very varied history. The first version ran on the HP 9000 Series 500 range of 32-bit machines based on the HP FOCUS multi-chip CISC processor. In 1984, the Hewlett-Packard Journal ran a detailed article on how that port was created, based on a kernel called SUN – not related to Sun Microsystems' SunOS. The Bitsavers site – run by Al Kossow, who recently recovered UNIX V4 from a 52-year-old tape – has a scan of HP's 1985 brochure [PDF].

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Then came a Motorola 68000 version, which ran on top of an AT&T Unix kernel, unusually stored in a ROM chip, in HP's pioneering portable Unix workstation, the HP Integral PC [PDF].

After that, it was rewritten again for HP's own in-house RISC architecture, PA-RISC. This was once a well-liked processor with its own native version of NeXTstep. At one point, Commodore investigated using it for a next-generation Amiga, the Amiga Hombre. However, the writing was on the wall for PA-RISC once HP announced it would be uniting with Intel's new EPIC architecture, as the infant Register reported all the way back in 1999.

For some time, both PA-RISC and Itanium versions were maintained more or less in parallel, until the last few releases, which were for the Itanium only. After that, the writing was on the wall and this news should not be too unexpected. Back in 2012, The Reg reported that the then-monolithic HP had started, then spiked, an x86-64 edition. Once that escape route was shut down and Itanium died, HP-UX was fated to die with it. Intel itself ended Itanium shipments in 2021 and with no new processors, that meant no new Itanium servers, and that left nothing new for HP-UX to run on.

A couple of years later, we covered the end of Linux on Itanium, but we're happy to report that we were wrong that nobody would keep maintaining it out of tree: the EPIC Linux project is still doing just that, and the T2 Linux distro still supports it. T2's lead maintainer, René Rebe, is also behind the Itanium support in GCC. ®