Red Hat Releases Linux 4.5 Update For Virtual Era


Even as Novell cozies up to Microsoft and Dell to make Linux and Windows play together better, Red Hat is doing what it can to make sure its older Linux versions are virtualization-friendly.

The Raleigh, N.C.-based Linux distributor has released Red Hat Enterprise Linux (RHEL) 4.5, an upgrade of its mainstream Linux platform that enables version 4.0 workloads to run in virtual machines on its latest version 5.0 release.

The beta version was released in February. Red Hat notified beta testers of the release of Enterprise Linux 4.5 on May 1.

Red Hat Enterprise Linux 5, which incorporates full support for the Xen virtualization hypervisor, was released March 14.

The upgrade won't enable Red Hat Enterprise Linux 4.0 distributions to host virtualization but will ensure that current 4.0 workloads can be migrated to virtual servers on the Xen-based RHEL 5 platform.

"What we are doing for RHEL 4 is to provide a modified kernel that will allow it to run as a paravirtualized guest. We're doing this because we can -- we own the operating system -- and because the performance gains make it worthwhile," said one Red Hat insider, who requested anonymity.

One partner who declined to be named said the update will ease the P-to-V migration process, allowing customers and partners to easily convert legacy physical (P) servers to virtual (V) servers running on new hardware and RHEL 5.

The update is necessary to enable current version 4.x workloads to run at peak performance on RHEL 5, the Red Hat source added.

"RHEL 5 is the only version that will host virtualization, and as a host, it will support guests. Guests can run fully virtualized, in which case they do not need to be modified in any way. The bad news is that fully virtualized guests don't perform very well," said the Red Hat source. "Alternatively, a guest can be paravirtualized, but this requires that it be modified. The good news is that a paravirtualized guest performs very well."

One Linux solution provider and Red Hat partner said customers are very interested in moving to version 5.0 because of the virtualization support and virtualization-friendly licensing arrangement.

"It's much less expensive for customers to deploy Red Hat Linux in a virtualized environment," said Ken Mclaurin, senior marketing manager of open source and virtualization services at Akibia, Westborough, Mass.-based. "Red Hat has changed the software licensing and made it economical for for customers to deploy multiple versions of Red Hat in a virtualized environment, whether it's Xen or VMware."