Download the authoritative guide: Cloud Computing 2018: Using the Cloud to Transform Your Business
Two years after a handful of IBM programmers in Germany first ported Linux to the IBM S/390, thousands of IT shops have downloaded free versions of the software from the Web. And more than 300 of these, according to IBM, are serious enough about the platform to have purchased hardware or support contracts from IBM specifically for Linux on the mainframe.
The level of interest has taken many by surprise, including IBM itself. "A year ago, honestly, we did not expect it to take off as it did," says Joann Duguid, IBM's director of Z-series Linux.
"Linux has been a huge breath of fresh air for the mainframe," says Giga Information Group analyst David Mastrobattista. "It's now politically correct to be talking about mainframes again in the data center."
Much of the interest in the platform is coming from companies which -- despite having spare cycles on their existing mainframes -- find themselves continually adding new Unix, Linux or Windows-based servers to their computer rooms to handle every-day computing chores like file, print and Web serving or email.
Running Linux under the VM operating system, these firms are discovering that they can bring up an essentially unlimited number of "virtual servers" on one mainframe, allowing them to consolidate many applications onto one system. That makes backup and administration much simpler and eases the pressure on crowded computer rooms which are running out of floor space, all the while taking advantage of the traditional high reliability and tremendous scalability of the mainframe.
Many of these companies are finding that the move is extremely simple. That was the case at Securities Industry Automation Corporation (SIAC), which runs the computer systems for the New York and American Stock Exchanges.
Last summer, SIAC moved a homegrown application off of Sun SPARC servers and onto an IBM zSeries mainframe running Linux. The program uses the open source Sendmail email program to deliver daily reports to Wall Street brokers on their stock transactions. According to IBM, the port took SIAC programmers only two-and-a-half days.
Slashing Application Costs
Another big draw of Linux on the mainframe is money. While Linux for the mainframe, and technical support, is available from companies like Red Hat, SuSe and Turbolinux, it can also be downloaded for free from the Web. And some companies, like recreational vehicle-manufacturer Winnebago Industries, of Forest City, Iowa, are discovering that Linux on the mainframe can slash the cost of application software licenses as well.
Two years, when Winnebago began looking for replacement software for its obsolete public domain email servers, which dated back to the 1980s, it turned first to Microsoft's Exchange Server. But the cost -- approximately $100,000 -- sent the firm looking for other options.
Last March, Winnebago began installing the Bynari Insight Server, from Dallas-based Bynari Inc., on its IBM Multiprise 3000 mainframe, under Linux. Today, Winnebago's 700 or so salaried employees, who use Microsoft Outlook as their email client, rely on the system for email and messaging, at a cost that Dave Ennen, Winnebago's Technical Support Manager, calculates to be roughly one-quarter of the price of buying Microsoft Exchange.
Winnebago had plenty of time to get comfortable with Linux on the mainframe. It first downloaded the software in September 2000, from the Web site of Poughkeepsie, N.Y.'s Marist College, which has served as a central liaison point for mainframe Linux. Since then, it has been using its mainframe and Linux for domain name serving, NFS, Samba and other utilities.
The success of those applications is leading Winnebago to consider moving other programs to the platform. "I'm done buying servers for a while," says Dave Ennen, Winnebago's technical support manager, "as long as I can find applications that run under Linux."
Those applications appear to be coming. IBM's WebSphere application server has run on the mainframe under Linux for more than a year, while SAP AG's mySAP.com e-business platform will be available in March. BMC Software's Mainview mainframe management tool was released in December, and Computer Associates has a number of products for the platform either in the pipeline or already out, including its flagship Unicenter data center management software.
"Not every application is available for mainframe Linux right now," says Mastrobattista, "but a good percentage of them are in the works. A lot of the independent software vendors are excited about Linux, and beginning to put resources toward porting things from Unix over to Linux."
Porting: "It can't be this easy"
Easing the process is the fact that the port appears to be fairly straightforward, at least for Unix applications. "When we took some Unix-based code and ported it to Linux on the Z-series, what we found was that it wasn't really a port," says Fred Johannessen, director of strategy for BMC's Linux initiative. "We just recompiled the thing, and it worked. We told ourselves, 'It can't be this easy,' but it really was that easy."
Other companies are not waiting for ISVs to port their products, but turning to open source software which is available for free. Newell Rubbermaid, a $6 billion a year housewares manufacturer based in Freeport, Ill., for example, is using Linux on its IBM S/390 mainframe to run an open source network monitoring program called Multi Router Traffic Grapher, or MRTG.
With some 44,000 employees globally, the firm's network links together company operations from Taiwan to Poland, says Paul Watkins, Newell's network analyst. The company was paying more than $6,000 each month to outsource the performance monitoring to an outside firm; now it uses spare cycles on its mainframe and MRTG to monitor the performance of thousands of ports on the company's Cisco routers, switches and other network devices.
Besides saving money on outsourcing costs, the application is allowing Newell to conduct the polling much more rapidly. Before, says Watkins, the company surveyed each device about once every half-hour, now, the mainframe's greater horsepower allows Newell to do it every ten minutes, and Watkins is aiming for near real-time monitoring. The company has just installed VM on the mainframe, and is investigating running other applications on the Linux partition.
"People said the mainframe was dead," says Giga's Mastrobattista, "but there's an estimated $1.3 trillion to $1.5 trillion worth of applications running on them. Those things just aren't going away. And today it's Linux which is really capturing the mindshare of people dealing with mainframes."
Dan Orzech is a Philadelphia-based writer specializing in technology. His work has appeared in the Los Angeles Times, the Philadelphia Inquirer, and many computer industry publications.