Two of IBM's oldest and most popular operating systems for its Power-based servers are being put out to pasture after years of service.
Last week, IBM said that it would be offering service extension on AIX 5.3, the operating system that was announced way back in July 2004 concurrent with Power5-based System p5 and i5 iron. AIX 5.3 was the first release of IBM's homegrown Unix variant that supported logical partitions (making a virtual machine that spans cores) and micropartitions (the ability to carve one core into as many as ten virtual machines); it also offered symmetric multiprocessing (SMP) shared memory that spanned up to 32 cores. The combination of AIX 5.3, decent Power5 iron, and very aggressive pricing put Big Blue on top in the Unix business.
IBM actually stopped selling AIX 5.3 back on April 29 last year, and offers AIX 6.1, launched in September 2008, and 7.1 – which debuted in August 2010 as the Power7-based systems were being rolled out – for licensing on current and prior Power Systems iron. IBM plans to cut off standard support on AIX 5.3 on April 30 this year. After that you will need to get extended support or move your AIX 5.3 to a workload partition.
Starting with AIX 7.1, IBM allowed the Unix operating system to carve up a virtual private server, called a workload partition, and run AIX 5.2 applications inside of this unchanged. This workload partition support for AIX 5.2 was important since none of the modern Power systems support this vintage operating system.
With an update of AIX 7.1 last fall, IBM added workload partitions that could emulate AIX 5.3 on top of AIX 7.1. And many customers will probably be taking a look at using this feature rather than buying extended support for AIX 5.3 proper. (A workload partition is distinct from a logical partition in that it creates one or more logically unique AIX 5.2 or AIX 5.3 instances that ride atop a single AIX kernel and file system; this is often called a type 2 hypervisor. IBM's logical partitions, or LPARs, run a complete AIX instance in each partition, which is managed by the PowerVM bare-metal or type 1 hypervisor.)
As you can see from IBM's AIX 5.2 and 5.3 lifecycle documents, the plan was to support the release for at least six year, then offer at least three years of extended support. After that runs out, IBM gives customers "help yourself" access to the tech support docs and AIX patches to self-support AIX 5.2 and 5.3.
With the AIX 5.3 service extension announced last week, IBM is offering Power Systems shops that want more hand-holding – and that are willing to pay an undisclosed sum for it – support for AIX 5.3 that gives customers on the most recent sub-releases (Technology Level 10, 11, and 12 in the IBM lingo) usage and bug fix support for an additional three years, running through May 2015. In the first two years, IBM will update AIX 5.3 twice a year and offer "toleration support" for "most new Power Systems hardware." What that means is that AIX 5.3 will run on Power7 and Power7+ iron, and maybe even Power8 iron, but it certainly won't be tuned to run as well as the current AIX 7.1 or the future AIX 8.1 to run on these machines. If you want defect support under this extended service contract, you need to be at Technology Level 12, the latest update for AIX 5.3.
On the proprietary side of the IBM midrange house – as if the Unixes were not as proprietary as z/OS, OS/400, OpenVMS, and Windows, but this is the language we inherited from the 1980s – IBM has announced the final support dates for its equally venerable i5/OS V5R4 operating system.
This proprietary operating system, which was the basis for much of the logical partitioning goodies that ended up in AIX 5.3 and the PowerVM hypervisor, came out in April 2007 and the plan originally was to sell it through January 2010. But just ahead of the Power7 system launch early that year, IBM pushed out the sales date for i5/OS V5R4 to May 2011 and kept peddling it because the move to IBM i 6.1 and 7.1 (as the OS/400 progeny are called) required a difficult and sometimes expensive program conversion for binaries before they could run on either of the more modern operating systems.
IBM hates the word recompilation in this case and it is technically not accurate, either. The AS/400 and its successors have a completely virtualized and abstracted view of the underlying iron and applications are compiled to this intermediate layer, not down to the iron. When these applications are run for the first time on a new piece of iron, the system compiles them down to the specific processors in the system under the covers. This approach gave the AS/400 the illusion of application compatibility, but every now and then – in this case, three times in the history of the line since 1978 – the underlying hardware is so different that the abstraction layer in microcode also has to be changed to make use of the new iron. This happened with the Power6 and Power7 servers and IBM i 6.1 and 7.1. And so, there is still a fair amount of i5/OS V5R4 out there in the IBM midrange installed base.
IBM stopped selling i5/OS V5R4 last year, but left open how long it would be supporting the operating system. Now we know: Standard support ends on September 30, 2013. And after that, IBM will offer extended support for roughly 1.7 times the cost of standard support for customers who need i5/OS V5R4 to stick around even longer. IBM has not made any commitments on how long this extended support term will last, but tells El Reg it is on the order of two to three years, depending on demand and costs. ®