I just read a press release from Sun Microsystems that presented VirtualBox 3.1 and its virtual machine migration capability, dubbed "Teleportation" by Sun. This product offers some interesting new wrinkles on virtual machine and virtual machine migration software.
Here are some snippets from Sun's release on VirtualBox 3.1
Sun Microsystems, Inc. (NASDAQ: JAVA) today announced a significant new version of Sun VirtualBox, its high performance, cross-platform virtualization software. VirtualBox 3.1 introduces the virtualization industry's first "Teleportation" capability, allowing running virtual machines to be moved, uninterrupted between disparate hosts - including those on different operating systems, different classes of computer (e.g. server to client) and even different CPUs (e.g. Intel to AMD). To download the freely available Sun VirtualBox software, visit: http://www.sun.com/software/products/virtualbox/get.jsp.
By adding Teleportation and significant performance increases to its already impressive SMP and large workload capabilities, VirtualBox 3.1 now exhibits a full complement of enterprise hypervisor features. Teleportation helps virtual machines achieve high availability. When physical hardware needs to be taken down, the virtual workload can simply be teleported to another physical host. VirtualBox 3.1 also improves execution speed, with optimized memory handling delivering performance increases of 30% over the previous VirtualBox release; network performance, delivering increased throughput, while reducing CPU cycles, through a new high-speed, paravirtualized network driver; and display performance via a new 2D Video Acceleration feature for Windows guests. In addition, VirtualBox 3.1 offers new more powerful snapshotting features that help administrators move a virtual machine back or forward in time to any arbitrary snapshot state.
A key component of Sun's industry-leading desktop-to-datacenter virtualization portfolio, VirtualBox is open source software and hugely popular: surpassing 20 million downloads worldwide since October 2007, with in excess of 40,000 downloads a day. A mere 50 megabyte download, VirtualBox software is incredibly compact and efficient and installs in just a few minutes.
VirtualBox software is free of charge for personal use. For wider deployments within an organization, enterprise licenses or subscriptions are also available, starting at $30 (USD) per user per year, which includes 24/7 premium support from Sun's technical team. Discounts are available based on volume. To sign up for an enterprise support subscription, visit: http://www.sun.com/software/products/virtualbox/get.jsp. For partners wishing to redistribute the VirtualBox technology as part of their own solution, Sun offers a comprehensive OEM licensing program.
Snapshot analysisLet's see, VMware has offered vMotion since 2004 and XenSource (now part of Citrix) launched XenEnterprise V4 that contained XenMotion in 2007. Now Sun is making a big deal of doing something similar five years after VMware and 2 years after XenSource.
I must point out that Sun has added some interesting scalability (e.g., number of processors/cores each virtual machine can use) and migration capabilities to VirtualBox.
It's pricing model for organizations, however may be seen as a "Sun Tax" on virtualization.