Virtualization occurs when a simulation replaces something that exists in the physical world. According to SearchServerVirtualization.com, “Server virtualization is the masking of server resources, including the number and identity of individual physical servers, processors, and operating systems, from server users. The server administrator uses a software application to divide one physical server into multiple isolated virtual environments. The virtual environments are sometimes called virtual private servers, but they also are known as partitions, guests, instances, containers or emulations.”
In data centers, virtualization is software driven, though some hardware is required. Virtualization software runs over or under other software, hardware and/or operating systems in order to create virtual devices. A virtualization layer is an abstraction layer, which masks everything under it, making it all appear more organized and unified than when each component is accessed separately.
What can be virtualized?
A few virtualization solutions are especially relevant and useful: Server, storage, desktop, networking, operating system (O/S) and application virtualization. Each type is similar.
O/S virtualization is considered the granddaddy of virtualization. It was information technology’s (IT’s) first foray back in the 1970s when mainframe systems were virtualized so multiple users could access the mainframe O/S. With O/S virtualization, the O/S behaves as if it were traditionally installed. In other words, a remote computer actually runs the various applications seen on your screen. In this way, your computer is only a terminal.
Network virtualization combines all of a network’s hardware and software components, presenting them as one entity that can be managed with the virtualization software. This action uses software to streamline multiple complex networks into one easy to understand and manage network.
Storage virtualization pools together all the physical storage components and houses them as though they were a single entity. It is managed by the virtualization software, which presents it all as a homogenous entity even though it most likely is not.
Desktop virtualization works for individual computers. It centralizes the primary operations and essentially feeds them to the user on an as-needed basis. Centered on virtual desktop infrastructure (VDI), the entire desktop computer is a virtual operation. The actual desktop environment, which includes the operating system, applications, etc., exists in the data center while a virtual version is pushed out to users. Some businesses appreciate this, as it lowers support costs. IT technicians do not have to run from computer to computer or cubicle to cubicle to fix a problem. Since everything is centralized in the data center, they can troubleshoot from there.
The virtual desktop can be a traditional PC, laptop or a thin client (a scaled-down version of a computer that does not have a hard drive and relies on the server for getting applications and programs).
The final type, application virtualization, looks like O/S, but only the applications are virtualized. In an office of 50 people, 50 copies of an application do not need to be installed. Instead, one copy is housed on a server and streamed out when someone needs to use it.
Finally, server virtualization has the fewest components. It occurs when physical servers are condensed through the virtualization layer. This means, with rough but achievable compression rates, 20 physical servers can be condensed down to one, and the original 20 physical servers will run as virtual servers. Only one server is installed and using power, but it can do the work of 20.
No slowing down
Most virtualization companies offer various products, and different types of the process can be combined, especially as technology advances. In this case, various elements of virtualization (O/S, storage, server, desktop, applications, etc.) would be part of the total virtualized solution.
Virtualization is rooted in common sense, logic and ease of management—highly sought-after traits for networked environments. The buzz and momentum is not slowing down, and those working in, around, near, for or with data centers and networked environments should try to understand it.
STONG-MICHAS, a freelance writer, lives in central Pennsylvania. She can be reached at firstname.lastname@example.org.