Ngoài ra để giảm chi phí, ảo hóa máy chủ mở ra cơ hội mới bằng cách cung cấp khả năng để dễ dàng tạo ra các hệ thống máy tính thích ứng và nhu cầu tăng năng suất của một tổ chức. Ảo hóa máy chủ không phải là câu trả lời cho tất cả các vấn đề kinh doanh, tuy nhiên, và một số hệ thống không | 124 Advanced Server Virtualization Disk Disk space and performance are as critical as processor and memory in its direct impact on guest virtual machine performance. The Microsoft recommendation of 2GB of available hard disk space does not take into account the disk space requirements of the virtual machines. As discussed in chapter 7 the proper way to size and evaluate hard disk subsystems is to provide adequate performance under varying loads. 1 Bear in mind that when virtual machines are launched they will consume additional physical hard disk space beyond just Thy jA that of their virtual hard disk file. With the release of Virtual Server 2005 R2 a blank saved state file .VSV is created when the virtual machine is launched. This file is the size of the memory being used by the running virtual machine. So if you have a virtual machine that has 512MB of memory reserved for it an extra 512MB file will be created on the host s physical disk. This will consume disk space that may not have been accounted for in your initial planning. Prior to the release of R2 this file would only be created when someone attempted to save state the virtual machine. With a pre-created saved state file in place during the launch of a virtual machine Microsoft could better guarantee that the user would be able to save the state of a virtual machine rather than find out when it is too late that the host server does not have enough disk space to accommodate the action. Network Microsoft host operating systems do not require permanent network connectivity however to perform any useful functions there should be one or more network cards present to deliver proper server class functionality. The specific details and options of the recommended configurations are provided in chapter 7. Display The minimum required graphics display card must provide at least 800x600 resolution and 256 colors. Although this is not recommended as it will be nearly impossible to administer the physical host server
