This post originated from an RSS feed registered with .NET Buzz by Jeff Key. Original Post: Virtual machine flavours Feed Title: Jeff Key Feed URL: http://www.asp.net/err404.htm?aspxerrorpath=/jkey/Rss.aspx Feed Description: Topics revolve around .NET and the Windows platform. Latest .NET Buzz Posts Latest .NET Buzz Posts by Jeff Key Latest Posts From Jeff Key

Bad-Ass MC Jon Galloway commented that he has a "friend" that isn't familiar with the differences between Virtual PC and Virtual Server. I've only used Virtual Server for a few hours, but rather than do some research for the facts, I'll tell you what I think I know.

Random points of interest:

• They use the same file format, so you can create a virtual machine with one product and use it with another.
• VPC supports sound cards, VServer doesn't.
• VServer supports SCSI disks, VPC doesn't.
• VServer supports multiple CD-ROM drives. VPC doesn't.
• VServer supports a few other server-like features, mostly relatively minor.

The big difference, though, is how they run: VPC runs as an interactive desktop process, whereas VServer runs as a service. VServer is designed to transparently function as a real machine on the network. Multiple virtual machines can be hosted by VServer in a single box.

Some of VServer's coolest features are at the service level. You can set constraints per virtual machine for things like relative processor utilization, absolute proc utilization, scripts that run based on a number of events, and so on. Administration is done via web pages, which I'm usually not very fond of, but they pull it off quite well. The admin pages display some stats for CPU utilization, disk & network I/O, etc. Like VPC, the admin site shows a thumbnail of the console screen, but adds a CPU graph that can be useful to see what's taxing your machine if you have more than one VServer running.

As I understand it, Microsoft bought the technology from Connectix for the server functionality. There are still many, many companies running their LOB apps on NT 4 and it's working just fine for them, thankyouverymuch. While software may continue to work well in an isolated environment, hardware doesn't fare so well. Things break, get more expensive to replace, cost more to manage, etc. The idea is that you can buy a new server box, a single Windows Server 2003™ license and throw all of your old NT 4 servers onto a single physical machine, completely isolated from each other in their own little 1996 worlds.

You don't need NT 4 to require application isolation. We've had bad experiences getting SharePoint to work on our current multi-use machines -- install fails, uninstall fails, then install fails to run again, leaving bits we don't want or need on (internal) production boxes. Creating a dedicated virtual machine is a no-brainer and has served us well. It, too, was trashed.