运行在虚拟服务器上的操作系统和应用程序不直接控制内存、硬盘和网络端口等资源，而是由位于 OS和应用程序之间的VM(虚拟机)截取与硬件交互的请求并在认为合适时对它们进行处理。 真正将此技术变成接近于魔术的是 VMware公司的ESX Server等世界级的虚拟化解决方案，这类解决方案能合成整个硬件的配置，而它与基础的硬件几乎没有关系。例如，宿主机可以最详细地模拟SCSI控制器的初始化过程，让客OS相信即使不存在物理的SCSI控制器时初始化也在被执行。它能使IDE磁盘机看上像SCSI磁盘机，能将网络共享的磁盘机转换成装在本机内的存储设备，将一个以太网卡变成几个网卡，并能在较老式的操作系统和它不支持的新式硬件(如光通道卡)之间生成网关。你可以建立完全适合应用程序需要的属于你自己的服务器，这时你用的是鼠标而不是用改锥。 在每次需要时把 OS 和软件装到物理的 PC 服务器是很烦人的。幸亏有了虚拟化你就不必这么做。在完全按你的喜好调好虚拟硬件的配置后，你就能把服务器磁盘映像保存到文件中，对其他的客系统而言它可以当做样板用。在实际中，它是一件赏心悦目的好事。你能通过拷贝该文件将虚拟服务器备份。复制该文件就能创建新的服务器 —— 而拷贝 Windows 需要重新激活和相应的许可证，或者把已有的服务器移到不同的物理硬件上。
Virtual Server
Server Virtualization is one of several rare, they sounded very good and it seems untrue, but in fact is true. Its early use is to reduce under-utilization of server hardware, (to deal with mission) into fewer machines. Since these early applications, it has developed into a multi-purpose solution to achieve higher reliability, better management, as well as enterprise data centers has become an indispensable tool for administrators. In accordance with a very simplified definition, the virtual server is the only use of an independent computer software to simulate the behavior and capabilities. The term virtualization is very simple. (Server Virtualization) software set at the bottom of the stack is directly installed on the server hardware, operating system, the ordinary. Is deal with their re-orientation and simulation of virtual layer, and re-orientation and constitute a virtual computer simulation. This is at the bottom two layers together are called the host. Host to provide everyone familiar with PC-BIOS ROM of the entire work, in accordance with the user's choice, use change user-defined a lot of preparation and give birth to an independent PC. As a physical server, virtual PC machine, only installed the operating system be useful. Installed in the virtual host's operating system, said a guest OS. Off the operating system installed (OS) is very simple, just from the OS installation from CD-ROM guide. This PC-installed OS is no different. Generally, if you do not know is how virtualization works, this is the answer: Just like a PC. In fact, in the whole Windows environment, you can easily find the North: in the look Windows host OS, or just watch the installation of the four Windows off an OS? May confuse you, but your customer OS and its applications are never made no mistake of. Each passenger OS think it has the whole machine. In a sense, it is to have the entire machine.
Software-based hardware
Running in a virtual server operating system and applications do not directly control the memory, hard drives and network resources such as ports, but by the OS and applications is located between the VM (virtual machine) that interacts with hardware interception of the request and when deemed appropriate, deal with them. Become closer to the real magic of this technology is that VMware's ESX Server, such as world-class virtualization solutions, such solutions can be synthesized throughout the hardware configuration, and it is based on the hardware and almost does not matter. For example, the host can be the most detailed simulation of SCSI controller initialization process so that customers believe that the OS does not exist even if the physical initialization of the SCSI controller also be executed. It can look like IDE disk drive SCSI disk drive, network share can be converted into the disk drive is installed in the local storage device, an Ethernet network adapter card into a few, and can operate in the more old-fashioned system and it does not support new hardware (such as the optical channel card) generated between the gateway. You can create complete applications for the needs of your own server, then you are using a mouse rather than using screwdriver. When necessary to each OS and software loaded into the PC physical server is very annoying. Thanks to virtualization you do not have to do so. Completely according to your preferences tuned virtual hardware configuration, you will be able to server disk image saved to the document, on the other passenger and systems it can use as a template. In practice, it is a pleasant thing. You can copy the file to virtual server backup. Copy of the document will be able to create a new server - and need to re-activate copies of Windows and the corresponding permit, or the server has been moved to different physical hardware.