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BOSTON—As expected, Red Hat Inc. announced Monday the release of its new top-end Linux: Red Hat Enterprise Linux 4, at a meeting with partners and customers at LinuxWorld here. What wasn’t expected was that Red Hat would come out firing at Sun Microsystems Inc..

Red Hat’s Paul Cormier, executive vice president of engineering, hammered home the point that customers like the Chicago Mercantile Exchange and online travel agency Orbiz have cut their costs by more than half while actually substantially boosting performance by switching to RHEL from Solaris.

Sun and Red Hat executives have been sniping at each other for months, even though the two are partners.

The battle of words began last April when Sun President and Chief Operating Officer Jonathan Schwartz said, “Red Hat has pretty much forked the distribution. This has given Red Hat tremendous gains for now, but ultimately it’s an impediment in the growth of Linux.”

For more on the war of words, read “Sun Sticks ‘Proprietary’ Label on Red Hat Linux.”

Red Hat partners including Advanced Micro Devices Inc., Dell Inc., Oracle Corp., Intel Corp. and Hewlett-Packard Co. were on hand at LinuxWorld to praise the release of RHEL 4. Sun was absent.

Scott Handy, vice president of worldwide Linux strategy for IBM, had especially kind words for RHEL 4—because it supports the entire IBM server line, from x86 servers to Z-series mainframes. With it, “we’re continuing to take market share from Sun and Solaris,” said Handy.

Cormier said the new RHEL will run RHEL 3-compliant applications, but with more stability and greater speed. He noted that, in particular, RHEL 4 showed well on 64-bit platforms like AMD’s Opteron.

This Linux is Red Hat’s first to be based on the Linux 2.6 kernel. It is largely based on Red Hat’s community Linux, Fedora 3.

Within the next four weeks, Cormier said, Red Hat Network, the Raleigh, N.C., company’s online support network, will be offering management services for Solaris.

The reason for this? “The reality is that customers are migrating from Solaris to Linux in larger and larger numbers, and we need to help them in their migration,” he said

“It’s the beginning of the end for Solaris in the enterprise,” said Cormier.

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