"In computing, virtualization or virtualisation (sometimes abbreviated v12n, a numeronym) is the act of creating a virtual (rather than actual) version of something at the same abstraction level, including virtual computer hardware platforms, storage devices, and computer network resources."
The study of creating virtual versions of physical resources such as servers, storage devices, and networks.
Types of Virtualization: This includes server virtualization, desktop virtualization, application virtualization, network virtualization, and storage virtualization. It is essential to understand these types to know which kind of technology is suitable for a particular task.
Virtualization Architecture: Understanding virtualization technology includes knowing its architecture. It comprises the physical hardware layer, the host operating system, the hypervisor layer, and the virtual machine layer. Knowledge of these various layers is crucial in determining how virtualization works.
Hypervisor: This is a layer of software that runs on physical hardware, and it is responsible for managing the virtual machine creation and allocation of resources. There are two types of hypervisors: Type 1 and Type 2. Type 1 is installed directly on the hardware of the system, while Type 2 runs on top of the operating system.
Virtual Machine Manager: This technology manages and monitors the virtual machines on the physical host system. It includes managing the virtual hardware for each virtual machine, modifying their configurations, and adjusting resource usage.
Resource allocation and management: This is essential to ensure that physical resources are allocated efficiently among the virtual machines. This includes understanding the use of processor cores, memory allocation, and disk space management.
High availability and disaster recovery: Implementing virtualization technology requires understanding how to implement high availability and disaster recovery measures to ensure that the system can handle hardware or software failures.
Virtualization Security: This includes understanding how to secure virtual environments, such as implementing access control policies, hardening the virtual machine, and securing the host system.
Cloud Computing: Cloud computing involves the use of virtualization technology to deliver computing resources over the internet. Knowledge of cloud computing is useful when implementing virtualization technology.
Application Compatibility: Understanding how to implement virtualization technology, and ensure that different applications can work in the virtual environment is essential.
Management tools: There are various management tools that can be used to monitor and manage virtual environments, including VMware vSphere, Microsoft Hyper-V, and Citrix XenServer. Knowing how to use these tools is essential to manage virtual environments.
Operating System Virtualization: It involves enabling multiple operating systems to run on a single physical machine. It allows for the creation of multiple virtual machines that can run various applications and operating systems at the same time.
Application Virtualization: It isolates software applications from their underlying operating systems and hardware dependencies. It allows for the creation of virtual environments that can run an application in a protective bubble, reducing conflicts, and simplifying software deployment.
Desktop Virtualization: It enables access to a virtual desktop environment, on a physical machine or through the cloud. It permits users to access desktop resources remotely, and IT administrators can manage virtual desktops from a central location.
Storage Virtualization: It enables the pooling of physical storage from multiple network storage devices into a single virtual storage device. It provides a way to manage storage resources across multiple devices, making it more straightforward for administrators to allocate storage capacity and accomplish data management tasks.
Network Virtualization: It enables the creation of virtual networks within a physical network, creating multiple virtual LANs (VLANs) that enable the isolation of network traffic. Network virtualization allows for greater network flexibility and ease of deployment, as it separates the physical network topology from the logical topology.
Hardware Virtualization: It enables multiple virtual machines to run on a single physical machine, providing an efficient way to utilize hardware resources. It allows virtual machines to share physical hardware resources like CPU, memory, and storage while also allowing them to be isolated from each other.
Cloud Virtualization: It provides virtual infrastructure, platforms, and software resources through the cloud, offering on-demand computing resources, scalability, and flexibility to organizations. Cloud virtualization allows for the creation of instances, virtual machines, and storage solutions, providing a cost-effective and efficient way of managing IT infrastructure.
Memory Virtualization: It enables the creation of a single view of physical memory across multiple physical machines. It provides the ability to manage memory in a more centralized way, allowing for a more efficient use of resources.
GPU Virtualization: It enables virtual machines and applications to access graphics processing units (GPUs) for high-performance computing tasks. It allows for the creation of virtual workstations, virtual desktops, and applications that can leverage the power of a GPU.
Virtualization Security: It provides a secure virtual environment through encryption, secured connections, and virtual network segmentation, which can protect against potential security breaches. It provides a secure platform for virtual environments to run and ensures data protection and privacy.
"Virtualization began in the 1960s, as a method of logically dividing the system resources provided by mainframe computers between different applications."
"An early and successful example is IBM CP/CMS."
"The control program CP provided each user with a simulated stand-alone System/360 computer."
"Since then, the meaning of the term has broadened."