Virtualization is a very complex topic, and there are a number of terms and words which are commonly used when talking about it. By becoming familiar with these terms, you will be better able to understand virtualization technology and reap the maximum benefits offered by it.
The first term that you will want to become familiar with is hypervisor. The hypervisor is the simplest component of virtualization. This is the software which is responsible for decoupling the OS, as well as the applications via the physical resources. The hypervisor comes with a kernel which is unique to it, and it must be installed right on the hardware, or the bare metal.
The hyper-visor will typically be installed among the OS and the hardware. Another term that you will want to become familiar with is the virtual machine. The virtual machine, known as the VM for short, is an operating environment which is self contained. The software works with the host OS, and it is independent of platform. It comes in the form of a CPU which runs code that has been compiled. The JVM, or instance, can operate an program which is based on Java. The VMs will need to be written for the operating systems which they function with.
The virtualization technologies may sometimes be referred to as being software which is related to dynamic virtual machines. Another buzz word that some people may have heard is paravirtualization. This is a form of virtualization in which the whole OS will run on the hypervisor, and it will communicate directly with it. This will result in a performance level which is much higher. The kennels for the operating system and the hypervisor will need to be calibrated, and this is done so that the interaction which is closed can be accommodated. The Linux OS is designed to that it is useful for working in an environment which is virtual.
Additional Virtualization Terms
The opposite of paravirtualization is full virtualization. With this type of virtualization, an abstract layer is presented which will intercept all the calls to the physical resources. Paravirtualization is dependent on a virtualized part of the x86 architecture.
Newer enhancements which have been made to the chips which have been made by both AMD as well as Intel are designed for virtualization. The best example of this is Pacifica by AMD, which is an extension that offers support for virtualization. It is designed for virtualization code which is much more simple, and it offers potential for a much higher level of performance.
This is especially true for environments that are heavily virtualized. Another term that is important to learn is application virtualization. Virtualization which occurs within the application layer will be responsible for isolating the software programs from both the OS and the hardware, and this basically allows them to be encapsulated in the form of independent objects which are moveable. These objects can be moved about without causing problems in the other systems. The application virtualization methods must be responsible for the minimization of alterations which are related to apps, and this is done for the OS.
The virtual appliance is not a type of hardware, as its name may imply. It is best described as an application which is prebuilt and preconfigured, one that is bundled with an OS within the virtual machine. The VA could be thought of as the vehicle for software distribution, and it is touted by VMware as being a method of configuring and installing software. The VA is responsible for targeting the layer for visualization, and it essentially needs a destination that has a hypervisor. The VMware has touted the VA as being a better method for packaging the software.
Xen and the CBA of Virtualization
Xen refers to the Xen Project, a program which was created to showcase an hypervisor which is open source. It has been offered since 2003 via the GNU license, and Xen functions on a host OS, and it considered to be on the cutting edge of paravirtualization technology.
When the project was first initiated, it was offered by a team at Cambridge University, and Ian Pratt, founder of XenSource, is the very first company to successfully implement a commercial edition of Xen. A sizeable number of firms now support Xen, and some of them include Microsoft and IBM.
The cost benefit analysis of virtualization is large. Many IT departments around the globe are being ask to do more with the same amount of resources. To deal with this situation, many IT departments are making use of virtualization.
Virtualization technologies offer a direct method of gaining the mandate through the collection of computing resources which are disparate, gathering them into pools which are shareable. The analysts show that the typical enterprise makes use of as much as 25% of the total capacity for the server. For these companies, much of the power is used up by the hardware.
By making use of virtualization technology, it is possible to consolidate x86 servers in a manner that allows time, energy, and money to be saved. The most powerful impact comes through the decrease in the amount of servers within the data center. A smaller number of machines means that there is a much lower level of power usage on a daily basis, and this includes both the servers and the systems used for cooling.
