Setting up multiple virtual machines in Virtual Server
Setting up multiple virtual machines
Setting up multiple virtual machines allows you to configure different combinations of operating systems and applications on one physical computer. Although this eliminates the logistics of setting up different physical computers, it introduces issues to consider as you plan the deployment. For example, some virtual machine settings affect how memory and storage space are allocated among virtual machines when they run simultaneously. In addition, several Virtual Server 2005 options affect performance. This topic describes the issues and considerations associated with setting up and running multiple virtual machines.
How multiple virtual machines affect settings
Some virtual machine settings can affect interoperability when virtual machines run simultaneously. The following table lists and describes the settings and how they are affected when you set up multiple virtual machines or run them simultaneously. Note that the table shows only the virtual machine settings that affect multiple virtual machines.
| Virtual machine setting | Description |
|---|---|
File name |
Each virtual machine must have a unique file name, which cannot contain any special characters and cannot be more than 150 characters long. The file name including the fully qualified path cannot be more than 256 characters. |
Memory |
Running more than one virtual machine at the same time requires at least enough memory for the host operating system and all guest operating systems running simultaneously. For more information about memory requirements, see System requirements for Virtual Server. |
Hard Disks |
Only one virtual machine can use a specific virtual hard disk at a time. |
CD/DVD Drive |
A CD or DVD drive may be captured by more than one virtual machine at a time. When a CD or DVD is inserted into the drive, the active virtual machine will automatically capture the CD or DVD drive. You can manually set other virtual machines to capture the CD or DVD drive by using the CD icon on the virtual machine status bar. |
Floppy Disk |
If you want to share a virtual floppy disk (.vfd file) between virtual machines, the .vfd file must be configured as read-only. For a physical floppy disk, the first virtual machine to detect the physical disk will be the only virtual machine that can use that disk. |
COM1 and COM2 |
Any device attached to a COM port may be used by only one virtual machine at a time. The device is not available to other virtual machines until the virtual machine is shut down or until it releases the COM port. |
LPT1 |
A device attached to the LPT1 (parallel) port may be used by only one virtual machine at a time. The device is not available to any other virtual machine or to the host operating system until the virtual machine is shut down. Physical LPT ports can only be used by a virtual machine if the port is using an I/O address range from 0x378 through 0x37F. |
For more information, see Setting Up Virtual Machines for Virtual Server.
CPU resource allocation
The options available on Virtual Server's CPU Resource Allocation page can affect the performance of the active virtual machine while other virtual machines are running in the background. These options allow you to control how physical CPU resources are allocated among the virtual machines and between the host operating system and guest operating system.
Other considerations
Following are some other considerations that apply when you run virtual machines simultaneously:
- Video settings
As you switch from one virtual machine to another, Virtual Server will require a short period of time to change the resolution for each virtual machine if the virtual machines are not all using the same resolution. - Switching between virtual machines
When running more than one virtual machine, you can use keyboard shortcuts to switch from one virtual machine to another, unless you are using full-screen mode. For more information about switching between virtual machines, see Switching between virtual machines and the host operating system.
For more information, see Setting Up Virtual Machines for Virtual Server.