Linked by Eugenia Loli-Queru on Sat 10th Dec 2005 19:28 UTC
Virtualization allows you to have multiple "virtual machines," each with its own operating systems running in a sandbox, shielded from each other, all in one physical machine. Each virtual machine shares a common set of hardware, unaware that it is also being used by another virtual machine at the same time. More here.
Permalink for comment 71258
To read all comments associated with this story, please click here.
To read all comments associated with this story, please click here.
Recent Original Stories
Recent Comments
Headlines
Random Comments
Random Stories
Random OS Link
Member since:
2005-10-25
I'm a developer. VMWare Workstation 4.x allows me to use a single laptop system to emulate an entire, hetrogeneous network with Fedora Core 3, Windows 2000, Windows XP, RedHat ES 4.0, and Windows 98, all on a single machine.
This does amazing things for my productivity, when I can test many different scenarios, including client/server apps, without ever leaving my single, lilliputian laptop!
Additionally, VMWare has a "snapshot" feature, where I can take a snapshot of the filesystem for a particular VM, (Virtual Machine) futz with it for a while, and then "roll back" to the snapshot after a virtual reboot. Very, very, very handy for testing software updates and installers, as well as "running it again"!!!
I can imagine where virtualization might be useful for high uptime situations, but that just seems a little wasteful to me in most scenarios. Using good quality hardware and a good quality O/S should result in uptimes exceeding a year without unplanned downtime. Day-to-day performance is a real bottleneck with virtualization. It degrades performance (and thus costs customers wait time) probably 25% to 50% or more.
In contrast, even without redundancy, using decent quality equipment and a reliable O/S, it's reasonable to expect less than 1 day of downtime in 2 years. That's about 0.14% downtime, far, far lower than 25%! So, virtualization for uptime fits in those scenarios where performance degredation is much less costly than minimal uptime. (not me!)