Korean Air said last week that it has moved its flight crew scheduling and daily revenue accounting systems to Linux running on an IBM mainframe at its Seoul headquarters. The 3,000 pilots and flight crew members will query the mainframe system to check the status of their assignments. In September, 5,000 users will be getting their scheduling information through the system, which can be accessed via a Web browser.
"This is one of the most high-profile uses of Linux in a mission-critical system," said Bill Claybrook, Aberdeen Group's research director for open source code. He estimated that there are a dozen mission-critical systems now in use on mainframes.
A growing number of other business users say they are willing to run their mission-critical business applications on Linux.
There have been about 3,000 downloads of mainframe Linux from sites such as Marist College's Web site or those of the Red Hat, SuSE and Turbolinux distributors, said David Mastrobattista, senior analyst of the Giga Information Group. About 10 of those downloads are running what he would call a mission-critical system "where the customer would see an impact if the system went down," he said. Roughly another 240 sites are developing or testing Linux for the mainframe, which IBM now calls the z900 server, he added.
Microsoft Senior Vice President Craig Mundie, who will deliver a keynote at the O'Reilly Open Source Convention in San Diego this week, called Linux and other open source code "a security risk" in a talk last spring.
But Linux is catching on. "In big business, the potential for Linux on the mainframe to displace many Intel servers is definitely there," said Arthur Tyde, president of Linuxcare, a San Francisco Linux technical support firm.
Household goods manufacturer Newell Rubbermaid has been running its Multi Router Traffic Grapher (MRTG) system under Linux on its mainframe for 10 months. It tracks the performance of 180 routers and 30 switches of the corporate network.
"MRTG under Linux has been very stable. It's worked the way it was supposed to," said Paul Watkins, Rubbermaid's network analyst.
Rubbermaid previously outsourced the same function and paid $6,000 per month. Watkins said he spent about 200 hours getting the Linux system up and running, but that it's now "pretty much self-sustaining". Rubbermaid purchased mainframe Linux for $180 from SuSE.
Winnebago Industries reduced its software licensing costs for email by 70 percent: the company consolidated different email systems into a single open source system, Bynari, running under Linux on an IBM mainframe.
Other users of Linux on the mainframe include the Banco Mercantile of Venezuela, Canadian application service provider coreFusion and Swedish telecom carrier Telia.
Linux on the mainframe "still has to catch on," said mainframe Linux user Tom Laudati, senior vice president of enterprise engineering of Infocrossing. Companies that already use a mainframe are the ones most likely to try it, he noted.
When asked about Mundie's warning of the risks associated with Linux, Laudati said: "I'm not sure what he meant. Linux goes through a lot of testing before we use it."
Rubbermaid's Watkins, a Microsoft-certified systems engineer, said Microsoft officials could talk about their own problems, rather than those of open source code. "Microsoft's NT was a good platform, but it had its share of problems," he said.
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