(02/26/2001) – If the “big three” industrial-strength versions of Unix had personalities, Hewlett-Packard Co.’s HP-UX would be the engineer, manipulating wireframe CAD files while crunching numbers from a lab experiment; Sun Microsystems Inc.’s Solaris would be the jock-turned-salesman, forever flexing its muscles; and IBM Corp.’s AIX would be the buttoned-down MBA who, while quietly clipping coupons and counting pennies, piles up a fortune that the others will never match.

In its typically quiet yet productive fashion, IBM is readying its next-generation Unix, AIX 5L, for an April release. The name alone indicates that the new version marks a radical departure from the current AIX 4.3.3: The L stands for Linux.

Financial and government IT operations are two of the most likely places to find AIX, followed by health care and e-business. Each of these areas is seeing increased adoption of Linux as a front-line system in IT operations. Linux is no longer just a developer’s playpen, and, for starters, AIX 5L’s Linux support means Unix shops will have a much easier time attracting developers and support staff, from a far hipper and bigger pool than was previously available.

Other enhancements in AIX 5L, including multipath I/O and NUMA (nonuniform memory access) support, stem from IBM’s role in Project Monterey, an effort shared with The Santa Cruz Operation (SCO) server software division (now part of Caldera) and Intel to develop an enterprise Unix to run on Intel’s perpetually forthcoming Itanium 64-bit processors. When Itanium does ship, it will be the final act that divorces the OS from the server platform, giving enterprises an option to buy servers from vendors that are not their OS vendors. Although Itanium’s arrival date continues to be “real soon now,” a lot of IBM’s work will pay off when AIX 5L ships on IBM’s current Power architecture this spring. A number of IBM’s RS/6000 machines will support AIX 5L upon release, which should help customers preserve their hardware investments.

Although Sun positions itself as the Unix leader, IBM expects to beat Sun to market with Java 2 Version 1.3 support in the OS and in its plans to offer an improved Workload Manager utility that supports disk I/O management in addition to familiar CPU and memory management features. Solaris currently lacks the ability to manage disk I/O, which can be an important way for IT managers to improve performance of Web-critical applications and allow more effective exploitation of unused server capacity.

As one might expect of a player in banking and government markets, security is a strong point for AIX. The current version, AIX 4.3, was the first 64-bit Unix to achieve TCSEC (Trusted Computer System Evaluation Criteria) C2 certification from the National Security Agency in the United States and the analogous E3F-C2 certification from Germany’s Federal Department for Security in Information Technology. We expect AIX 5L will achieve similar ratings. With enhancements from third parties such as Argus and Bull, AIX can also be beefed up to Common Criteria 2.0 B1 certification. These are the kinds of systems that attackers ignore in favor of easier prey.

Don’t let the L for Linux confuse you; this will be IBM’s beefiest AIX ever. Folding Linux support into AIX, a sign of serious commitment to Linux, does not compromise IBM’s investment in AIX. If anything, IBM is going to be walking the walk as well as talking the talk. Although new installations will be an obvious place to deploy AIX 5L, we predict that customers will want the Linux features and other enhancements so much that they will upgrade with little coaxing.

P.J. Connolly is a senior analyst in the InfoWorld Test Center covering networking, security, and server technologies.



Business Case: IBM’s AIX may lack the flashy marketing of other Unix families, but it makes up for it by consistent quality in all areas. If scalability, security, and stability are sore spots for your operations, AIX 5L may prove to be the cure for what ails you. IBM’s support for Linux also means that your company can employ the hottest developers and administrators to build enterprise-class applications.

Technology Case: Linux has gradually infiltrated the enterprise, and IBM has figured out that it’s better to be holding the reins than just jumping on the bandwagon. Itanium support, an improved JFS2 file system, and networking and security enhancements combine to make this not only the toughest AIX ever but also a very attractive alternative for those looking to make a break from Solaris and Sparc.


+ JFS2 offers the potential for petabyte-size file systems

+ Linux compatibility features improve application portability

+ AIX supports both RISC-based Power and forthcoming Itanium processors


– IBM hardware still lags behind Sun’s and HP’s in number of CPUs and is behind HP’s in total memory supported

Prices listed are in Cdn currency.