Part One of this article appeared yesterday.

Small shops the clearest winners
The DCCA and Sabre Holdings examples show the longer-term promise of mainframe migration for large IT infrastructures. But according to Forrester’s Phil Murphy, smaller shops -- especially those that use their mainframes primarily as application servers -- can make the best case for migration today. These small-scale mainframe environments are typically less complex than one like Sabre’s, for example, yet they still cost significantly more than equivalent distributed systems.
Vestcom, a company that prints and distributes financial statements on behalf of banks and brokerages, is a prime example. A quarter of its IT budget went to pay for hosted services on an IBM System/370 mainframe running VMS, which provided about 150 MIPS of computing power.
Vestcom used the mainframe to download huge quantities of data, apply various formatting and calculation rules, then create and print the statements. But as revenues plummeted following the dot-com crash and a series of accounting scandals, the company needed to lower costs quickly. Vestcom CIO Joe Mislinski says the mainframe was an easy target.
Mislinski hired Micro Focus to port Vestcom’s Cobol code to a quad-processor x86 server. Sticking with Cobol as its application language allowed Vestcom to reduce the number of variables in the transition, but some things just didn’t translate.
Case in point: The mainframe could handle very large jobs and recover at any point in case of printer failure. In the new environment, however, tasks were distributed as several parallel sub-jobs, each going to independent printers. If a printer failed, there was no master job image that the software could use to recover from the interruption point.
“But none of this was insurmountable,” Mislinski says. Vestcom ended up creating its own management tools to track the status of each sub-job on each printer, making it possible to reconstruct job status in case of failure at any point.
IDC analyst Josselyn notes that transitions away from the mainframe typically encounter such issues, as job management and recovery were solved in the mainframe world long ago and are now often taken for granted. Vestcom was helped by the fact that it found a hosted-services vendor that supported both the mainframe and distributed-system environments. That way, if the migration didn’t work it would still have a backup option.
Vestcom spent $1 million on its mainframe migration, which Mislinski says he’ll recoup in two years, based on operational savings. The modern PC interface also enables his operations staff to respond to customer requests in just half the time it took previously, he estimates. Plus, having the code on a Windows platform means his staff can take advantage of visual development environments. It also means his Cobol programmers are now working in the same environment as his C# coders, so they can cross-train each other.
No mass exodus
Despite these companies’ successes, migrating away from the mainframe is expensive and risky for most organisations. That’s why IDC and Forrester Research see real interest in less than five percent of enterprises surveyed. It’s also why IBM still gets nearly $5 billion a year in zSeries mainframe sales, notes IDC’s Josselyn. He says the attitude he encounters most from IT is, “If it’s not broken, why fix it?”
Josselyn says IBM has adjusted some of its licensing fees to address the issue of high licensing costs. And, Forrester’s Murphy advises, even users of orphaned mainframe technology -- languages such as PL/I or hardware such as ICL’s or Bull’s -- can still modernise their mainframe technology, rather than dump it, by deploying Cobol, C++, and Java applications on Unix partitions. That strategy at least will let IT rationalise its environment and make any later transition to distributed systems easier.
Also, although the desire to move from legacy programming languages with a dwindling supply of developers is a common secondary motivation for mainframe migration, both Murphy and Josselyn note that Cobol developers' salaries have not increased in recent years, indicating no shortage.
Meanwhile, however, system vendors have dramatically improved the reliability and scalability of distributed systems to the point that enterprises can consider x86- and RISC-based servers running variants of Unix, Linux, or Windows for mission-critical applications.
Josselyn says the area in which these platforms still have a disadvantage is in management, because workload, latency, and data management can become difficult as you scale to hundreds of servers. Murphy suggests though, that this situation may improve in the next several years, as vendors deliver better tools and as IT staffs learn to run the systems the mainframe way, using techniques such as virtualisation.
Enterprises with small mainframes or those that use them primarily as application servers -- the Vestcoms of the world -- are the most likely to begin wholesale migration to other platforms. Larger organisations are more likely to off-load some services and reduce the variety of mainframe systems in their portfolios while still taking full advantage of their available mainframe MIPS to keep per-transaction costs down, says Mike Gilbert, vice president of marketing at Micro Focus.
The first step is to decide which kind of organisation you are, then to really think through what should continue to run on the mainframe and what should be migrated elsewhere. The good news is that the time is ripe to finally make that migration happen. The Big Iron Age is by no means over, but the first signs of the Distributed Age are definitely here.