Kernel-based Virtual Machine (KVM) virtualization is an emerging technology in the open source market.
Canonical's Ubuntu Server Edition operating system was the first major Linux distribution to offer a fully functional KVM virtualization stack, and Red Hat Enterprise Linux (RHEL) followed about a year later. If you're interested in this virtualization technology, should you use Red Hat or Ubuntu KVM?
Red Hat vs. Ubuntu operating systems
Before answering this question, let's look at the distributions themselves. RHEL is the major enterprise Linux distribution; Fortune 500 data centers all over the world use it. It runs mission-critical, high-performance applications, including Oracle database and middleware products and Red Hat's own JBoss line.
Ubuntu Server is an entirely different ball of wax. Canonical Ltd.'s recent Ubuntu Server Survey revealed that Ubuntu is still used primarily on self-assembled PCs -- typically for Web, mail and database servers (i.e., the traditional LAMP stack). Still, Ubuntu has the potential to grow to the enterprise level. The question, however, is whether its management capabilities qualify Ubuntu KVM for enterprise-level prime time today.
There is no difference between the underlying Red Hat and Ubuntu KVM virtualization technologies. Red Hat acquired Qumranet, the company that develops KVM, but it is still open source technology. All features developed by Red Hat will appear in Ubuntu KVM sooner or later, and vice versa.
Red Hat vs. Ubuntu KVM implementations
Red Hat and Ubuntu KVM virtualization differ in terms of best use case, however. On Ubuntu Server the big theme is cloud computing, and Ubuntu Enterprise Cloud, powered by Eucalyptus Systems, has been integrated with the OS since version 9.04.
Customers that need virtualization don't always need a cloud, though, so Ubuntu KVM might not be an option for everyone. If you look beyond the cloud, Ubuntu KVM offers only basic tools such as virt-manager and virsh, which all work on the libvirt library. But Ubuntu KVM may not be best suited to an enterprise environment.
Red Hat, on the other hand, has further developed its KVM implementation with its Red Hat Enterprise Virtualization for Servers and Red Hat Enterprise Virtualization (RHEV) Manager for Servers products. RHEV Manager for Servers manages virtual environments and can compete with other management platforms, including Citrix Systems Inc.'s XenCenter and VMware vCenter Server. It offers high availability, live migration, storage management, a system scheduler and more.
Red Hat also actively develops new virtualization tools and technologies. Examples include oVirt, a Web-based management platform for virtual environments, and libguestfs, a file system for virtual machine images. Thanks to these contributions and the RHEV for Servers product line, the company has positioned itself as a leader in KVM virtualization.
Although Ubuntu KVM shows promise, these advances make Red Hat the only KVM virtualization option you should take seriously.
About the expert
Sander van Vugt is an independent trainer and consultant based in the Netherlands. Van Vugt is an expert in Linux high availability, virtualization and performance and has completed several projects that implement all three. He is also the writer of various Linux-related books, such as Beginning the Linux Command Line, Beginning Ubuntu Server Administration and Pro Ubuntu Server Administration.