The SWsoft-funded OpenVZ project Monday released its OS-level server virtualization software in the form of a kernel build for Red Hat Enterprise Linux 4 (RHEL4), plus enhancements that the company said will provide users with additional flexibility.

For example, now OpenVZ virtual environments can be called by designated names, rather than simply numeric IDs. Also, it is now possible to set the number of processors available to specific virtual environments for more granular performance tuning.

The RHEL4 kernel build is said to improve support for new hardware such as the latest gigabit Ethernet and SCSI adapters. The OpenVZ software release includes:

-- Checkpointing and live migration -- it freezes a virtual environment and stores it for restoration on another server.

-- Virtual Ethernet device support -- allows network devices to be created inside virtual environments using designated names and hardware addresses that are different from the actual physical device.

"We continue to set a fast pace of software delivery to make available better and better technology with more and more capabilities," said project manager Kir Kolyshkin. "Within the past two weeks, we announced OpenVZ as part of the Debian distribution and now we're providing an update with more value for the user community."

OpenVZ technology is built on Linux and enables multiple virtual machines - or virtual environments as the project calls them -- atop a single kernel. According to OpenVZ, this enables greater server utilization and superior availability with fewer performance penalties. The virtual servers ensure that applications do not conflict and can be re-booted independently.

SWsoft is the developer of the Virtuozzo virtualization product.