version 4 is the first time Red Hat's commercial product includes the newer 2.6 kernel, or heart, of Linux. Although Red Hat's previous version included some 2.6 features, it was Novell's that was first to include the full list last August, including improvements to communications and memory subsystems.
But Red Hat doesn't appear to have lost ground. "Novell made such a big deal that Red Hat was trailing with the 2.6 kernel. This was going to give SuSE a big entree into enterprises in the United States," said Illuminata analyst Gordon Haff. "That really doesn't seem to have happened."
Robert Frances Group analyst Stacey Quandt agreed. "The customers waited, overall," she said.
Red Hat announced the new product Tuesday at the LinuxWorld Conference and Expo here, but executives discussed the product on Monday.
Paul Cormier, Red Hat's executive vice president of engineering, said one major new feature with RHEL 4 is the inclusion of Security Enhanced Linux, or SELinux. That feature----allocates privileges for various computing processes in a more detailed way, making it harder for an attacker who compromises one part of a system to take over the entire machine.
SELinux is enabled by default, with strict security settings for software that provides network services, for example the Apache software for hosting Web sites, Cormier said.
The new version also includes theWeb browser; Logical Volume Manager (LVM) 2 to let storage systems be spread across multiple hard drives or confined to fractions of hard drives; a connector to retrieve e-mail from Microsoft Exchange servers; support for serial ATA hard drives; and the ability to detect most digital cameras.
The Raleigh, N.C.-based company also is expanding its Red Hat Network management service so it can control servers running. Customers wanted a management tool that could be used while they migrate from Solaris to Red Hat Linux, Cormier said.
Although Sun ships Red Hat with its x86 servers, the company is aggressively promoting Solaris as its preferred option, and it's begun making it an open-source project as well to better counter Linux.
RHEL 4 is available for 32-bit and 64-bit x86 processors such as Intel's Xeon and Advanced Micro Devices' Opteron; Intel's Itanium; and IBM's Power-based and mainframe computers. Versions are available for desktop computers, workstations, low-end servers with one or two processors, and high-end servers with four or more processors.
RHEL 4 will run software written for RHEL 3, Cormier said.
Pricing, which covers annual support subscriptions, is unchanged compared with RHEL 3. For example, a one-year subscription RHEL 4 ES for a dual-processor server costs with standard support costs $799, while a year of RHEL 4 AS for a four-processor server and premium support costs $2,499.
Red Hat also sponsors a free product, called, which lacks long-term support and hardware and software certifications. That version will be at the center of the Fedora User and Developer Conference here on Friday after LinuxWorld winds down.