InnoTek VirtualBox User Manual
Chapter 1. Introduction
InnoTek VirtualBox is a family of virtual machine products targeting desktop computers, enterprise servers and embedded systems. Due to its modular architecture, VirtualBox can be deployed in any environment where x86 systems are to be virtualized on x86 systems. (With “x86″, we are referring to 32-bit CPUs from AMD and Intel as well as compatible CPUs from other vendors, plus 64-bit CPUs in 32-bit mode.) 1.1. Virtualization basics VirtualBox allows you to run unmodified operating systems — including all of the software that is installed on them — directly in a special environment on top of your existing operating system. This environment, called a “virtual machine”, is created by the virtualization software. The physical computer is then usually called the “host”, while the virtual machine is often called a “guest”. VirtualBox allows most of the guest code to run unmodified, directly on the host computer, and the guest operating system “thinks” it’s running on real machine. In the background, however, VirtualBox intercepts certain operations that the guest performs to make sure that the guest can cooperate with other programs on the host. The techniques and features that VirtualBox provides are useful for several scenarios:
- Operating system support. With VirtualBox, one can run software written for one operating system on another (say, Windows software on Linux) without having to reboot. You can even install in a virtual machine an old operating system such as DOS or OS/2 if your real computer’s hardware is no longer supported.
- Infrastructure consolidation. The full performance provided by today’s powerful hardware is only rarely really needed, and typical servers have an average load of only a fraction of their theoretical power. So, instead of running many such physical computers that are only partially used, one can pack many virtual machines onto a few powerful hosts and balance the loads between them. This can save a lot of hardware expenses. VirtualBox is unique in the virtualization market in that it can run virtual machines as mere servers for the Remote Desktop Protocol (RDP), with full client USB support. This allows for consolidating the desktop machines in an enterprise on just a few RDP servers, while the actual clients will only have to be able to display RDP data any more.
- Testing and disaster recovery. Once installed, a virtual box and its virtual hard disk can be considered a “container” that can be arbitrarily frozen, woken up, copied, backed up, and transported between hosts. On top of that, with the use of another VirtualBox feature called “snapshots”, one can save a particular state of a virtual machine and revert back to that state, if necessary. This way, one can freely experiment with a computing environment. If something goes wrong (e.g. after installing misbehaving software or infecting the guest with a virus), one can easily switch back to a previous snapshot and avoid the need of frequent backups and restores.
InnoTek VirtualBox User Manual
