Thinking outside the box is overrated, says the OpenVZ group; its server virtualization technology lets you create mini networks of virtual machines inside a single large physical server. But what if the time comes to move to a new box?
The OpenVZ project recently released new software that gives server administrators the ability to migrate a virtual server image from one physical machine to another without disrupting access to the virtual machine throughout the entire process.
OpenVZ says its latest software, based on the 2.6.9 Linux kernel, allows admins to freeze the state of a virtual machine environment, in production, and move that image to another physical machine while the original environment continues to serve users and communicate with other systems. OpenVZ says this is a better way to move a virtual machine environment than previous methods, such as: moving all data from one virtual machine storage; reinstalling applications and software on a new machine; then shutting down the fist machine and bringing the up the second.
Getting back to that "inside-the-box" idea, the new OpenVZ software also allows users to create virtual Ethernet devices within the physical server used for a virtual machine environment.
The software's creators say this feature is different from the peer-to-peer style virtual network device that is set up to connect a virtual server environment to the physical machine's host operating system (or to connect virtual servers to each other). Virtual Ethernet allows users to set up virtual network devices with their own Media Access Control (MAC) addresses. This allows users to create microcosms of switched IP networks inside one machine. Users can set up a DHCP inside the virtual environment for other virtual devices. VLAN segmentation, access controls and other networking features can be set up inside this environment as well, according to the software's makers.
Get the latest OpenVZ code here.