Server virtualisation refers to splitting up the physical server into many virtualised private servers by means of a software called hypervisors. Each virtualised server works independently of others having their own operating system and resources. VPS Hosting utilises this concept to provide users with virtual servers having allocated resources. 

Types of Server Virtualisation

There are three approaches to server virtualisation, and is based on the level of virtualisation each provides:

1. Machine level virtualisation: Also known as full virtualisation, as it gives the utmost isolation. Each virtual environment runs its own operating system and as an autonomous server. It utilises the host-guest paradigm, where the guest is unaware of the host operating system. However, a hypervisor is used as the management layer between the guest and the host to direct instructions to the CPU.
2. Paravirtual machine: This model involves porting, which is a modification of the guest’s operating system by the hypervisor. It is better suited for scenarios which require multiple virtual machines. Popular examples of software which uses paravirtual machines include Xen and UML. 
3.  OS level virtualisation: In this model, the host and the guests use the same operating system. However, different versions of the same operating system can be installed. Examples of OS layer virtualisation are Virtuozzo and Solaris Zones. 

Advantages of server virtualisation:

1. Reduced expenditure: Server virtualisation not only help in saving on capital expenditure but also reduces operational expenditure. Since the hardware size is reduced, there is lower energy consumption which adds in lower overall cost. This is why a Linux VPS Server is a cost-effective solution for businesses who are not yet ready to purchase a complete physical server. 
2. Automation: With virtualised servers, many operations could be automated. This eliminates the need to hire more people. The savings on them provides an added advantage. 
3. Reliability:  Virtualisation provides a more reliable backup and recovery option. This is a must-have feature, especially with the rise in cyberattacks. Linux VPS Server provides security which can guard the server against cyberattacks. One-click recovery can restore the server in the previous best state. 
4. Scalability: As virtualisation offers to choose the resources as per the requirements, it is an ideal solution for businesses who are looking to scale. Without having the need to invest in servers which are not going to be used, one can just pay for their requirements. 

Choosing the right technology:

The two popular technologies that use server virtualisation are KVM and Virtuozzo.

1. KVM or Kernel-based Virtual Machine is open-source and hardware-based virtualisation. It uses require Linux operating system but can also support other OSs such as Windows and Solaris.
2. Virtuozzo is a container-based which utilises OS-level virtualisation. It runs a single OS kernel as its core. 

Conclusion:

Server Virtualisation is an emerging and popular technology that will continue to develop with technological advancement. It allows you to have dedicated control over your server, and you can choose between KVM and Virtuozzo based on the level of control required. VPS Hosting offers one of the most cost-effective server virtualisation benefits. You can migrate to VPS Hosting for a reliable, scalable, and affordable virtualised server space.