VPS web hosting

A virtual private server (VPS, also referred to as Virtual Dedicated Server or VDS) is a method of splitting a server. Each virtual server can run its own full-fledged operating system, and each server can be independently rebooted. The practice of partitioning a single server so that it appears as multiple servers has long been common practice in mainframe computers, but has seen a resurgence lately with the development of virtualization software and technologies for other architectures.

Virtual private servers bridge the gap between shared web hosting services and dedicated hosting services, giving independence from other customers of the VPS service in software terms but at less cost than a physical dedicated server. As a VPS runs its own copy of its operating system, customers have superuser-level access to that operating system instance, and can install almost any software that runs on the OS. Certain software does not run well in a virtualized environment, including firewalls, anti-virus clients, and indeed virtualizers themselves; some VPS providers place further restrictions, but they are generally lax compared to those in shared hosting environments. Due to the number of virtualization clients typically running on a single machine, a VPS generally has limited processor time, RAM, and disk space.

Due to their isolated nature, VPSs have become common sandboxes for possibly-insecure public services or update testing. For example, a single physical server might have two virtual private servers running: one hosting the production-level (live) website, and a second which houses a copy of it. When updates to crucial parts of software need to be made, they can be tested in the second VPS, allowing for detailed testing to be conducted without requiring several physical servers.

Virtual private servers are also sometimes employed as honeypots, allowing a machine to deliberately run software with known security flaws without endangering the rest of the server. Multiple honeypots can be quickly set up via VPSs in this fashion.

Different Types of Virtual Private Servers

There are 2 kinds of virtualisation: software based and hardware based.

Software based virtualization

the virtual machines share the same kernel and actually require the main node's resources. Within a hosting environment this aids in real time quota incrementing and decrementing without having to restart the node. Within software based virtualisation, the main examples are Virtuozzo (an SWSoft product), and HyperVM (an lxlabs product), and VMWare (a VMWare product).

Hardware based virtualisation

the virtualization mechanism partitions the actual or real hardware resources thus removing the ability to modify burst or real-time quota modification. These limits are thus hard, and the systems need to be restarted for any modification to function. Although it has a glaring deficiency it does tend to be a little more secure and thus useful in an enterprise usage.

Some examples of paravirtualization-capable hypervisors are Xen, Virtuozzo, Vserver, and OpenVZ (which is the open source and development version of Parallels Virtuozzo Containers).Hybrid or partial paravirtualization, is full virtualization, but in which the guest uses paravirtualized drivers for key components such as Networking and Disk I/O, resulting in greatly increased I/O performance. As such, it is a common solution for operating systems which cannot be modified (for various reasons) to support paravirtualiztion.

As cost effective as a shared server

Partitioning a single hardware server into multiple servers has been around for a long time. In fact, mainframe computers have long been partitioned into multiples. By sharing the resources you are able to get far more 'bang' for your proverbial 'buck'.

With VPS Hosting you therefore combine the benefits of both shared hosting and dedicated hosting allowing you to virtually run your own virtualized server at a fraction of the cost!