Thursday, February 12

Overview of virtualization technologies for VPS

Overview of virtualization technologies for VPSEven a cursory examination of proposals for the lease VPS striking abundance of visualization offered by the host.
Among them are the Open VZ, Virtuozzo, Xen, KVM, Microsoft Hyper-V, VDS manager and various modifications to these technologies. Each provider brings a lot of pros use it his system, but few compare visualization technologies with each other and talking about the cons.

In this paper we fill this gap and objectively consider the basic visualization technology used hoster that will help beginners make the right choice of renting a virtual dedicated server.

Software and hardware visualization
Visualization technologies used in hosting can be divided into two types - soft and full visualization (hardware) visualization. The first group include OpenVZ, Virtuozzo, VDS manager, while the second - Xen, KVM and Hyper-V from Microsoft.

Software visualization involves visualization at the kernel level of the operating system (OS): all virtual machines share a common modified kernel server. At the same time the user each virtual machine looks like a separate server.

Because you are using a common core OS on virtual machines can only use this kernel. When it comes to Linux VPS on the basis of software visualization technologies - VPS users available on any Linux distribution to choose from (Cent OS, Debian, Ubuntu, etc.). If we are talking about Windows VPS - users can only rely on the server with the same version of Windows, which is installed on the hyper visor. Today, it is usually a Windows Server 2008.

Undeniable advantages of visualization software - the speed of the virtual machines. Creating VPS, re install OS, server load, and similar operations take even a minute, and second. In addition, due to the saving of resources nodes the kernel is loaded once and is used by all VPS, VPS cost of such lower than the cost of VPS-based technologies with full visualization

.Cons - not enough rigid division of resources and the possibility of overselling. However, at the present level servers used for visualization, this issue comes to naught. A typical configuration of today's server visualization as follows:
Processors: 2 x Intel Xeon E5620 (8 physical cores)
RAM: 48-96 GB of ECC Reg
Disk system: 4 x 450 GB SAS Hardware RAID 10 (about 5 times more productive than SATA-drives)