Sunsets on the 31-bitish Empire

by Hesh Wiener

If you want IBM support for your mainframe operating system and you're not already using a 64-bit zSeries processor, it's crunch time. IBM is winding down support for versions of its operating systems that run on 31-bit systems. But wait, there's less: IBM is dropping its low-cost ESL (Entry Server License) software pricing for mainframes with up to 8 MIPS. And it's even said it will confine support for its VSE operating system, a favorite of small (but numerous) mainframe shops, to a handful of platforms within two years.

If you want to scare yourself now, before you read one more word, here's a summary of IBM's systems software sunset plans. Take a gander at that table.

For users with very modest MIPS requirements, the time to make choices is running out. While IBM offers brand new z890 machines geared down to run with as little as 26 MIPS capacity, as this other table shows, the cost of one of these computers can be, well, impractical. But so is conversion to one of the other platforms, including systems in all the other IBM product groups.

Small mainframe shops that are running a bunch of custom legacy applications have to move ahead, migrate, or figure out how to manage without IBM's software safety net. There are no universal answers, because these shops are as unique as snowflakes. But it's not too hard to catalog the challenges and it's even possible to find a few common elements that might form the basis of a strategy.

First, a small shop with legacy applications and an aging mainframe has to see just what it costs to bring in a new IBM mainframe and move to systems software that will be around for a while. IBM or one of its resellers will be happy to provide that information down to the last penny, with one possible exception: It may be hard to pin down the cost of forward migration.

A new z890 might have the right power for a user who requires at least 26 MIPS, but quite a few shops with mainframes that are under 200 MIPS use IBM systems with internal disk storage and the z890 doesn't include disks. So, right away the user of a Multiprise 2000 or Multiprise 3000 will have to add the cost of a disk subsystem to the bill.

There may also be some work required to get running applications set up under a new operating system. Some users can get a firm price quotation. Others will get a rough range of costs. Still others will find out that any help they need is going to cost whatever it works out to based strictly on consulting time.

All of this might work out just fine. But even if it does, it's probably wise for every user who is looking into an IBM systems software sunset to ask the question IBM cannot answer: What if this shop doesn't want to (or simply cannot afford to) move to the front?

It's possible for a mainframe shop to get by without an IBM software contract, particularly if the record shows that there was really no crucial need for this support for quite a while. Users who don't change their systems software or middleware and who only maintain their data and applications may find that IBM support is comforting, but it's no longer a vial lifeline. Also, a shop running "unsupported" software runs into a problem that's beyond its in-house skills, IBM really won't refuse to help; it will just hook the user up with its services group, which will have hotshots that can support just about anything. Also, IBM isn't the only source of systems expertise, not by a long shot. There are plenty of companies and individual systems software consultants working the low end of the IBM mainframe base, and the odds are they are less costly per hour than IBM's services team. Finding people you trust is another matter, but that's the case with plumbers, electricians, car mechanics, dentists, doctors, and, well, the list doesn't end, does it?

A small shop that has decided not to move to a zSeries box for now, and wants to wait at least until used machines become affordable, should really look at its workload and its installed mainframe to make sure they match. If some applications have been moved to another platform our out to a services company, this might be a good time to downsize. In that second table I created, you can see that there are plenty of hardware choices under 200 MIPS. And every one that's got less power than an installed machine probably has lower software costs. You might have to do a little arithmetic to get hard numbers, but it shouldn't be to hard to figure out how much you might save by moving down a notch or two and compare it to whatever it might cost for the work and hassle of moving your system to a different box.

For the very smallest shops, it's just about the end of the line for IBM's most inexpensive mainframe platform, machine type 3006, also known as the S/390 Integrated Server. It's really an Intel server with a mainframe on a card, but in most respects it's a scaled down Multiprise running at about 8 MIPS. It even has internal disk drives.

IBM licenses software for this computer at very low rates, as you can see in this table, or at least it will if you get started by the end of 2005, when the ESL plan ends. Not only that, IBM will still sell you one of these machines used, which once listed for 50 grand. IBM says you can have a working S/390 IS 3006 for $6,000 on its Web site. And there are independent outfits that offer complete packages including migration of data and applications to the mini-mainframe, which is an idea worth considering, as the S/390 IS 3006 has a personality all its own. It's a favorite of shops that have brought in an alternative platform but find that a handful of remaining legacy applications are just murder to move. IBM will maintain this mainframe for $537 a month, an aspect of the machine that makes it an easy step for some users, at least until they decide whether they want to bring in less costly third party maintenance.

Last but definitely not least, there are a few companies selling IBM approved emulated mainframes, machines based on xSeries servers, SCO Unix, and the Flex-ES mainframe emulator. As it stands, IBM has said it will sunset operating system support on these boxes about the same time as it pulls the plug on support for Multiprise 3000 platforms, but the Flex people point out that their code is approved by IBM for hosting of 64-bit operating systems in the developer community. It ought to be possible for an intrepid user to stretch the boundaries a bit, but not necessarily on the cheap. The support costs for a Flex box can be higher than for used IBM hardware with at least as much power, and this can offset software license savings. A lot depends on the software stack at a particular site. For some shops, Flex is a real bargain, for others an interesting but not compelling choice.

So, while IBM usually gets mainframe users to see things its way, perhaps because they don't have any other viable options, there are still dozens, maybe hundreds of small shops that are going to look for alternatives.

RELATED RESOURCES

A summary table of IBM's systems software sunset plans

A table showing the cost of small IBM mainframes

A table of ESL software license fees