As more companies embrace virtualization, it's important to be up to date on the topic. Below we'll discuss some of the common and less common instances of virtualization and why they are valuable.
This is most common type of virtualization used today, hardware virtualization is common because of the advantages it offers concerning hardware utilization and application uptime. It typically refers to virtualizing a server.
Normally, a server devotes complete control of it's hardware resources (cpu, RAM, and storage) to the actions of a single operating system. When you virtualize your hardware, it means that a program called a hypervisor manages the hardware's resources and divides them among different isolated operating systems, referred to as “virtual machines.”
By separating your Hardware among multiple operating systems, there is a greater diversity of programs that can be utilized without encountering compatibility problems. It also prevents a single application crash from impacting everything else that is running on the server. Before virtualization, it was fairly common for servers to utilize less than 30% of their available hardware resources. Thanks to these improvements, modern companies can utilize nearly 100% of the hardware investment they make.
Another advantage to hardware virtualization is the portability it offers. With modern hypervisors an IT team can migrate running virtual machines from one server to another - allowing them to do updates and maintenance without ever having downtime for the application. Preventing downtime is important for larger businesses that lose significant amounts employee productivity (wasted salaries) or sales when an application is down.
Desktop Virtualization separates the desktop environment from the physical device that is used to access it. This is most often configured as a “virtual desktop infrastructure” (VDI) where many personal desktops (say Windows 10) are run as virtual machines on a server, but employees access those desktops from client devices (generally PCs).
The advantage to Desktop Virtualization is in work convenience and information security. Because the desktops are accessed remotely, an employee is able to work from any location and on any PC. This creates a lot of flexibility for employees to work from home and on the road without needing to physically bring their work computer. It also protects important company data from being lost or stolen by keeping it in a controlled location on their central servers.
Similar to VDI mentioned above, application virtualization differs in that it delivers only a specific application from a server to the user's device. Instead of logging into an entire desktop, the user will interact with the application as though it were a native application on the client device. This makes application virtualization preferable for work on tablets or smartphones because the native presentation makes working easier.
The big advantage to application virtualization is efficiency. In many situations where remote applications are useful, applications are redundant across employees. With that in mind, running an entire operating system for each employee becomes unnecessary if you can simply run a separate instance of the application.
Imagine an office where the employees chiefly use Microsoft Office programs - it makes much more sense to have a single server or virtual machine run the Operating System and just deliver the applications to each employee as they need them.
Application virtualization is normally done using Windows Server and Windows Remote Desktop Services. However, some of the hassles of setting it up have lead to a number of third party virtual application delivery softwares that simplify management and improve user experience.
Storage virtualization improves storage flexibility by creating a unified virtual pool of storage from physical storage devices in a network. What this does is present all physical storage in a cluster as a single shared group - visible to all servers.
Storage virtualization is important because it allows for virtual machine portability without necessitating a shared storage array (generally a NAS or SAN). Under normal circumstances powerful virtualization features like live migrations and high availability require expensive share storage arrays to operate. By using storage virtualization, every server added to the network contributes to the virtual storage pool as though it were a SAN or NAS array.
Network Virtualization (sometimes referred to as Software-Defined Networking)
Similar to storage virtualization, network virtualization pools resources from all physical networking equipment and presents it to virtual machines and applications as a single virtual network.
This increases network agility and drastically reduces provisioning time for new network architectures. What once involved physically connecting devices and then configuring each device to properly communicate is now done virtually in moments (both manually and through automated templates).
Additionally, network virtualization improves the amount of visibility an IT team has into the network since everything is managed from a central platform. It also allows for better virtual machine portability (network architecture is preserved) and for impressive new security features like a distributed firewall (a firewall at each virtual machine).