VPS Hosting Blog

A virtual private server is a method of dividing a physical server computer into multiple servers that each has the appearance and capabilities of running on its own dedicated machine.

The practice of slicing up a single server so that it appears as multiple servers has been common practice in computers, but has seen reappearance lately with the development of virtualization software and technologies for other architectures.

By virtualization software installation we can runs a program that boots each virtual server from a disk image within a virtualization environment.

TYPES OF VIRTUALIZATIONS
•    SOFTWARE BASED

In a software based virtualization environment, the virtual machines share the same            kernel and actually require the main node’s resources. Virtualization by software             normally has many benefits in a web hosting environment, due to quota increasing and decreasing in real time without restarting the node.

Some of virtualization software’s are-
o    Virtuozzo (a product of swsoft.com)
o    HyperVM (a product of lxlabs.com)
o    Vserver
o    OpenVZ

•    HARDWARE BASED
In this virtualization, the virtualization mechanism divides the real hardware resources. In this there is no burst and/or real time quota modification is possible; the limits are hard and can only be modified by restarting a virtual machine instance. This virtualization mechanism is potentially more secure in the sense that it is less subject to “Quality of Service crosstalk” between virtual machine instances. Its security is typically dependent on the correctness of a larger and more complicated Trusted Computing Base.
Some of the Hardware virtualizes are Microsoft Virtual Server, VMware ESX Server, and Xen.

USE OF VPS HOSTING
Virtual private servers is a intermediate type of 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. But VPS generally has limited processor time, RAM, and disk space.
Due to their isolated nature, VPS have common sandboxes for possibly-insecure public services or update testing. When updates to critical parts of software need to be made, they can be tested in the second VPS, allow for thorough testing to be conducted without several physical servers.
Virtual private servers are sometimes used as a device to deliberately run software with known security flaws without endangering the rest of the server.

VIRTUALIZATION SOFTWARE
There are several different pieces of software that handle the task of virtualization.
•    User-mode Linux
•    VMware
•    Microsoft Virtual Server
•    qemu
•    VDSmanager
•    Virtualbox
•    xensource
•    Parallels
•    OpenVZ
•    HyperVM
•    Virtuozzo
•    FreeVPS
•    FreeBSD jail
•    Solaris Containers (Zones)