Virtual server is a space created within one powerful physical server. On a single physical machine (running on one hardware), there can be more separate virtual servers. They share the processor, memory and disk capacity, but they are separated by means of dedicated virtualization software while maintaining full security. A virtual server acts like a real computer with its own operating system.
You are most likely to encounter the term when you are looking for rental of your own server provided by some hosting services. Virtual server is the foundation of hosting or cloud computing services. In these areas, they are a very widespread, cost-effective and safe option. The user’s environment on the host server is well isolated from other environments which means that changes in one environment do not affect the other ones in any way. This is the task of a virtualization software. A virtual server is reserved for its user and it works just as any other server.
What are the options?
Hosting providers offer basically the following options (offered under different commercial names):
- Virtual managed servers (VMS) - administrated by the hosting provider. They are intended for lay users or companies that don’t want to burden themselves with the basic administration of the server. However, it also involves accepting certain technologies (such as operating system or database system that is offered and administrated by the hosting company). They are often used for webhosting. Sometimes they are referred to as cloud services.
- **Virtual Private Server (VPS) - administrated by the clients themselves. With VPS, you decide what you want to run on your servers (operating system, database, etc.). Sometimes they are also referred to as “full control”. The use of VPS allows you to avoid the purchase of your own hardware, however, you are in charge of all server-related administrative work.
What is the virtual server used for in practice?
Virtual servers are used to save capacity of physical servers which is an expensive one. Thanks to server virtualization, multiple virtual servers can be run on one “iron”. This is because hardly any application uses the total of the sever performance at all times and, therefore, the hardware performance can be shared between multiple software. The virtualization software ensures that operations of one software do not obstruct operations of other software. For example, one server can host a virtual server run on Windows, another one run on Linux, each of them using a totally different databases and so on. Virtual servers act as if they were running on different machines. Therefore, the company does not rent hardware, it only rents a virtual server, ie. a virtual environment.
Virtual servers are used to run several business applications each of which needs a different environment. Also, they are used for testing - after various configurations have been tested, the virtual servers are simply shut down. Another equally important aspect of using virtual servers is the enhanced security against various cyber attacks since the virtual server creates an extra tier of security.
The existence of virtual servers has been enabled by the rapid development of information technology in recent years thanks to which the machine performance has been greatly improved. Previously, server barely managed to perform the task for which it was designed. One of the key pioneers of virtual servers is VMWare.
Virtual servers are the technological basis of HaaS (Hardware as a Service) and IaaS (Infrastructure as a Service) services. Also, Virtual computer works on a similar basis.