Chapter 5 - Virtual Machines

Abstract

This chapter discusses the different components of the virtual machine and how to create them. The creation of virtual machines and the loading of both Microsoft and alternate operating systems were covered along with the use of the Virtual Machine Additions. There are four different kinds of virtual disks. The four types of virtual hard disk are: Dynamically expanding, Fixed-size, Differencing, and Linked. Each has its own function and by combining the different types is possible to create a basic operating system disk. Adjusting the memory, disk, CD/DVD, floppy disk drive, and network adapters all combine to create the virtual server. One important thing is that all virtual machines are dependant on the physical resources of the Virtual Server 2005 server. The host server must have enough physical resources for memory, disk, CPU, and network bandwidth to handle the number of virtual machines and the allocated resources of each. Adding hardware to the server can add additional capacity and performance to the host computer. Adding faster processors or additional processors, memory, and NIC cards, and disk subsystems are the primary resources that will increase the capacity of the Virtual Server host computer. All the virtual machines are single-processor machines but a multiprocessor host computer can run many more virtual machines than a single-processor host. Using a host operating system that can support larger memory capacities and multiple processors are good choices for production host computers. Virtual Server 2005 supports the major Linux distributions and provides Virtual Machine Additions for Linux to help improve their performance and operation on the host computer.