Virtualization refers to the act of creating a virtual version of something, including virtual computer hardware platforms, storage devices, and computer network resources. In simple words, it refers to running more than one Operating System on a single physical hardware. An easy example to understand this is, partitioning a single hard drive into two hard drives. This way there are ‘virtually’ two hard drives but in reality, there is only one.
What is Server Virtualization?
Server virtualization is the process of creating multiple server instances from one physical server. Each server instance represents an isolated virtual environment. Within each virtual environment, you can run a separate operating system.
A single server can only use one operating system (OS) and is usually dedicated to a single application or task. This is because most applications do not function effectively together on a single server. Because of this, much of a server’s processing capabilities go unused. However, when a server is virtualized it is transformed into multiple virtual servers which can each run different operating systems and applications in an isolated environment. This means less wasted processing power. The benefits of server visualization are :
- Higher server ability
- Cheaper operating costs
- Eliminate server complexity
- Increased application performance
- Deploy workload quicker
Three Kinds of Server Virtualization
- Full Virtualization: Full virtualization uses a hypervisor, a type of software that directly communicates with a physical server’s disk space and CPU. The hypervisor monitors the physical server’s resources and keeps each virtual server independent and unaware of the other virtual servers. It also relays resources from the physical server to the correct virtual server as it runs applications. The biggest limitation of using full virtualization is that a hypervisor has its own processing needs. This can slow down applications and impact server performance.
- Para-Virtualization: Unlike full virtualization, para-virtualization involves the entire network working together as a cohesive unit. Since each operating system on the virtual servers is aware of one another in para-virtualization, the hypervisor does not need to use as much processing power to manage the operating systems.
- OS-Level Virtualization: Unlike full and para-virtualization, OS-level visualization does not use a hypervisor. Instead, the virtualization capability, which is part of the physical server operating system, performs all the tasks of a hypervisor. However, all the virtual servers must run that same operating system in this server virtualization method.
Why to use Server Virtualization
Virtualization is an ideal solution for small to mid resource usage applications. Some of the reasons to use server virtualization are:
- Virtualization helps in preserving space, as several resources share the same physical space owing to the partition. This also helps in effective resource management.
- Virtual Servers offer users the privilege of the dedicated server but at a less price. This is helpful in case of small and medium-sized businesses that do not require the whole dedicated infrastructure and resources.
- Backing up of data is simple thereby preventing data loss.
Server Virtualization is growing and will continue to grow with the advances in technology. Server virtualization has come a long way in the last two decades. The necessity and importance of server virtualization will be more prominent in coming days.