VPS hosting, or Virtual Private Server hosting, is a way of hosting websites by partitioning a server into multiple “virtual” servers so that each virtual server has the abilities and appearance of running on a dedicated machine. A virtual server can have its own operating system that need not be the same as other virtual servers on the same machine, and each virtual server can be rebooted independently of the others. This creates a great amount of flexibility for website hosting companies and for those needing web hosting. Using virtual servers, although the term wasn’t used then, has often been implemented on large mainframe computers so multiple users could make use of the same machine. Recently, virtual servers have found new use as web hosting tools.
How does VPS hosting work? Well, once the actual physical server is booted up, it starts a program that creates a virtualization environment for each virtual server and then “boots” that server. These environments are similar to emulators in that each one is an operating system running inside another operating system. None of these virtual servers have direct access to any device or piece of hardware connected to the physical server. Each has to send commands to the physical server and be given access to the hardware to use it.
There are two different types of VPS hosting: a hardware based type and a software based type. Software VPS hosting means that the virtual machines all share the same kernel and all make use of the server’s resources. This has a number of different benefits, especially in the web hosting world. Different resources and priorities can be changes in real time without restarting anything. This type of VPS hosting software includes Vserver, OpenVZ, and Xen.
Hardware based VPS hosting, however, actually partitions off the hardware resources. This does not allow for any real time modification, and any changes don’t take place until the virtual server is restarted. In some ways, these virtual servers are more secure, but they also require more complicated environments. These types of servers include VMware ESX Server and Microsoft Virtual Server.
No matter which type of VPS hosting you use, you’ll find that they offer a number of benefits. VPS hosting is something of a cross between shared hosting and dedicated hosting. You have the low cost and resources a shared web host supplies, but you have all the flexibility of a dedicated web host. You can control all aspects of your operating system, even deciding which system to use. You can install just about any piece of software, too, although there are some programs such as anti-viruses and firewalls that don’t work so well in virtual environments. Note that since many different clients are using the same resources, VPS hosting usually has a limited amount of disk space, RAM, and processor usage time. However, this isn’t really any different than shared hosting.
