HP-UX

HP-UX

Company type	Proprietary software
Industry	Operating systems
Founded	1984
Founder	Hewlett Packard Enterprise
Headquarters	United States
Products	Unix-based operating system
Website	https://www.hpe.com/us/en/servers/hp-ux.html

HP-UX—short for "Hewlett Packard Unix"—is a proprietary Unix-based operating system created by Hewlett Packard Enterprise. Its latest releases are compatible with HPE Integrity Servers that utilize Intel's Itanium processor architecture. Originating from Unix System V (initially System III), HP-UX made its debut in 1984.

Previous iterations of HP-UX were designed to run on the HP Integral PC and the HP 9000 Series 200, 300, and 400 platforms powered by Motorola 68000 CPUs. It also supported the HP 9000 Series 500 systems built on HP's proprietary FOCUS architecture, as well as later HP 9000 Series models employing HP's own PA-RISC instruction set. Notably, HP-UX was a pioneer in implementing access-control lists for managing file permissions as an alternative to traditional Unix permission schemes, and it was among the earliest operating systems to integrate a native logical volume manager.

For an extended period, HP collaborated with Veritas Software, adopting the VxFS as its principal file system. HP-UX is one of only three commercial operating systems certified under The Open Group's stringent UNIX 03 standard, alongside macOS and AIX.

Following the phase-out of Itanium processors, HP has announced plans to retire HP-UX by December 2025.

Characteristics

HP-UX 11i incorporates a shared disk architecture tailored for its clustered file system environment. The clustering capabilities are provided through HP Serviceguard, while workload optimization is managed by HP Global Workload Management. This system dynamically adjusts workloads and integrates with Instant Capacity on Demand, enabling customers to pay for additional resources in increments as short as 30 minutes during periods of peak usage.

The operating system offers virtualization at the OS level, supporting hardware partitions, isolated OS virtual partitions on cell-based servers, and HP Integrity Virtual Machines (HPVM) across all Integrity server models. On HP-UX 11i v3, HPVM can host guest operating systems including Linux, Windows Server, OpenVMS, and other instances of HP-UX itself. Additionally, live migration of virtual machines is possible with encryption protocols ensuring data security throughout the transfer process.

Scalability on a SuperDome 2 running HP-UX 11i v3 extends to:

• Up to 256 processor cores
• As much as 8 TB of main memory
• Maximum supported file system size of 32 TB
• Maximum individual file size up to 16 TB
• Support for 128 million logical units, each capable of handling up to 8 zettabytes (ZB), totaling an aggregate capacity of 16 million ZB

Security

The release of version 11i v2 brought significant security improvements including kernel-level intrusion detection, enhanced random number generation, protection against stack buffer overflows, security partitioning mechanisms, role-based access control (RBAC), and incorporation of various open-source security utilities.

HP organizes its security offerings into three main categories: data protection, system safeguards, and identity management:

Category	Security solutions
Data	Encrypted Volumes and File Systems, Trusted Computing, whitelist-based controls, containerization technologies, IPsec
System	Software Assistant utility, Bastille hardening framework, Auditing System tools, IPFilter, Host Intrusion Detection System (Host IDS), Standard Mode Security Extensions
Identity	Role-Based Access Control (RBAC), PAM-integrated Kerberos, AAA (RADIUS) server support, Kerberos authentication server

Files dependent on context

The introduction of context dependent files (CDF) occurred in release 6.x alongside 3.x, allowing a fileserver to distribute distinct configurations, executables, and architectures tailored for diverse clients within mixed environments. Directories containing CDFs were marked with the suid bit and remained hidden from standard processes, a characteristic occasionally misused by attackers to mask harmful software. The CDF system and its filesystem were phased out starting with release 10.0.

Hardware platforms supported

HP-UX is compatible with multiple PA-RISC hardware models. With version 11.0, support expanded to include Integrity servers, easing the transition from PA-RISC to the Itanium architecture. The initial support for Itanium appeared in HP-UX 11i v1.5, while version 11i v2 provided compatibility with both CPU architectures.

BL server blades

HP-UX 11i accommodates HPE Integrity BL server blades that utilize Intel's Itanium processors.

CX server series

The CX server line from HP, intended for telecom applications and featuring -48V DC power along with NEBS certification, is supported by HP-UX 11i versions v2 and v3. These servers employ Itanium Mad6M CPUs but have since been discontinued.

RX server series

Support for HP's RX series servers is also provided within HP-UX.

Chronology of releases

Prior to version 11.11, HP employed a decimal-based versioning format denoting major and minor updates. Beginning with 11.11, a marketing-oriented naming convention was adopted, labeling releases as 11i followed by v(decimal-number). The i symbolized Internet capabilities, resulting in a dual approach to version identification.

Detailed version timeline

Version	Release date	End-of-life date	Supported hardware
Template:Version	2000-12-01	2015-12-31	HP 9000
Template:Version	2002-06-02		Integrity
Template:Version	2003-10-01		HP 9000 and Integrity
Template:Version	2007-02-01	2021-03-31	HP 9000
Template:Version		2025-12-31	Integrity
Template:Version

Release versions

1.0 (1982)

Launched for the HP 9000 Series 500, built atop a Series 500-specific OS named SUNOS (unrelated to Sun Microsystems' SunOS).

1.0 (1984)

Based on AT&T System III; supported the HP Integral PC (HP 9807A). Kernel executed from ROM.

2.0 (1984)

Debuted for HP’s Motorola 68000-based workstations including the HP 9816U, HP 9826U, and HP 9836U.

5.0 (1985)

Based on AT&T System V; available for Integral PC, Series 200/300, and Series 500 models. Introduced proprietary Starbase graphics API and HP Windows/9000 windowing environment for Series 300.

3.x (1988)

Designed exclusively for HP 9000 Series 600/800; developed concurrently with the 5.x/6.x lines before unification at HP-UX 7.x.

6.x (1988)

Targeted Series 300 systems only; incorporated sockets derived from 4.3BSD, introduced context dependent files (later removed in release 10), and replaced HP Windows/9000 with X11.

7.x (1990)

Supported Series 300/400 initially and later extended to Series 600/700/800 platforms. Delivered OSF/Motif support and was the final release to include HP Windows/9000.

8.x (1991)

Compatible with Series 300/400/600/700/800 hardware; introduced shared libraries.

9.x (1992)

Supported Series 300, 700, and 800 systems; launched System Administration Manager and Logical Volume Manager (LVM). Adopted the Visual User Environment desktop interface.

10.0 (1995)

Unified workstation and server OS for Series 700 and Series 800 respectively, retiring older product lines. Standardized system files according to AT&T’s SVR4. Introduced Software Distributor packaging tools and LVM support extended to Series 700.

10.10 (1996)

Added the Common Desktop Environment alongside UNIX95 compliance.

10.20 (1996)

Enabled support for 64-bit PA-RISC version 2.0 processors; integrated Pluggable Authentication Modules (PAM) within CDE and introduced Veritas File System (VxFS) support for root filesystems. Support concluded in June 2003.

10.24

Released as Virtual Vault, enhancing security through compartmentalized file access that limited superuser privileges.

10.30 (1997)

Developer-focused release adding kernel threads based on a one-to-one threading model.

11.00 (1997)

First to provide native support for 64-bit addressing while maintaining compatibility with legacy 32-bit applications. Added symmetric multiprocessing capabilities, Fibre Channel support, and NFS PV3 enhancements.

11.04

Another iteration of the Virtual Vault security enhancement release.

11.10

Limited distribution supporting HP 9000 V2500/V2600 SCA servers with JFS version 3.3, AutoFS integration, updated ftpd daemon, and scalability up to 128 CPUs.

11.11 (2000) – branded as 11i v1

Introduced Operating Environments—pre-packaged application bundles optimized for categories such as Mission Critical, Enterprise, Internet, Technical Computing, and Minimal Technical usages. Added features including hard partitioning, Gigabit Ethernet support, NFS over TCP/IP, loadable kernel modules, dynamic tunables, kernel event notifications, and protected stacks.

11.20 (2001) – known as 11i v1.5

Marked initial support for Itanium IA-64 platforms though lacking ServiceGuard clustering functionality at launch. Enabled execution of PA-RISC applications on Itanium systems and supported Veritas Volume Manager version 3.1.

11.22 (2002) – referred to as 11i v1.6

Enhanced Itanium-specific release featuring scalability up to sixty-four processors, an m:n threading model, expanded dynamic kernel tunables, plus Logical Volume Manager compatibility on Itanium hardware.

11.23 (2003) – labeled as 11i v2

Debuted with Itanium architecture support initially while subsequent updates incorporated PA-RISC compatibility, ccNUMA architecture features, web-based kernel/device configuration tools, IPv6 networking stack enhancements, and improved random number generation mechanisms.

11.31 (2007) – designated as 11i v3

Provides dual-platform support for PA-RISC and Itanium systems including native multipathing capabilities, unified file caching mechanisms, NFSv4 protocol support, Veritas Cluster File System integration, multi-volume VxFS functionality, built-in virtualization through HP Integrity Virtual Machines technology, and hyper-threading on selected Itanium processors. Complies fully with The Open Group’s UNIX03 specification.

HP-UX 11i Operating Environments

HP provides HP-UX 11i through a collection of bundled packages known as Operating Environments (OEs).

The current lineup for HP-UX 11i version 3 includes:

Base OE (BOE)

This package delivers the complete HP-UX 11i operating system along with file system tools, partitioning utilities, and applications focused on web hosting, system administration, and security. It integrates software that was previously offered separately or included within FOE and TCOE bundles.

Virtualization Server OE (VSE-OE)

Incorporates all BOE capabilities plus GlancePlus for performance monitoring, software mirroring, and the full suite of Virtual Server Environment components such as virtual partitions, virtual machines, workload management, and capacity advisory tools.

High Availability OE (HA-OE)

Enhances the BOE by adding HP Serviceguard clustering for failover support, cluster management utilities, GlancePlus performance analysis, and software mirroring functions.

Data Center OE (DC-OE)

Merges the complete features of both HA-OE and VSE-OE into a single comprehensive package designed for virtualization alongside high availability. Disaster recovery solutions and compiler collections are offered separately.

Support for HP-UX 11i version 2 ended in December 2010. The available OEs for v2 were:

Foundation OE (FOE)

Aimed at web and front-end server environments, including the HP-UX Web Server Suite, Java platform, and Mozilla Application Suite.

Enterprise OE (EOE)

Builds upon FOE by adding applications such as the GlancePlus Pak to enhance enterprise server capabilities.

Mission Critical OE (MCOE)

Expands EOE with MC/ServiceGuard clustering and Workload Manager to support large-scale back-end applications and transaction servers.

Minimal Technical OE (MTOE)

Tailored for workstation use, featuring Mozilla Suite, Perl scripting, VxVM volume management, Judy arrays, and the OpenGL Graphics Developer's Kit.

Technical Computing OE (TCOE)

Extends MTOE by incorporating advanced graphics programs, MPI support, and mathematical libraries suited for computation-heavy tasks.

HP-UX 11i version 1 remained available until December 2009 with extended maintenance support continuing at least through December 2015.

See also

• HP Roman-8 (character encoding)

References

• Scott W. Y. Wang and Jeff B. Lindberg, "HP-UX: Implementation of UNIX on the HP 9000 Series 500 Computer Systems", Hewlett-Packard Journal (vol. 35, no. 3, March 1984)
• Frank McConnell, More about the HP 9000, gaby.de
• Hewlett-Packard Company, "HP-UX Reference, Vol. 1, HP-UX Release 6.5, December 1988", HP Part no. 09000-90009

External links

• Official HP-UX Homepage
• HP-UX Software Updates & Information