Virtualization is a standard practice in enterprise IT today, as its extensive applicability helps not only lessen vendor lock-in but also forms the foundation of cloud computing. The rise in popularity of virtualization over the years can be credited to it enabling enterprises to partition their servers and run legacy applications on more than one operating system type or version. But, what is virtualization?
What is virtualization?
Virtualization is the creation of a simulated computing environment in contrast with a physical environment. It refers to technology where applications, guest operating systems or data storage are abstracted from the actual underlying software or hardware. Virtualization enables users to build effective IT services from resources that are traditionally bound to hardware.
Virtualization allows organizations to partition a physical computer into many virtual machines. This enables organizations to run several operating systems, applications and virtual systems on one server. As a result, organizations enjoy increased performance, greater availability of resources, greater mobility of workloads and automated operations. The various types of virtualization include network, storage, data, server, application and desktop virtualization.
Benefits
An advantage of using a virtualized environment is that disaster recovery is made easier. In such an environment, the backup and recovery of virtual machines is made feasible by consistent snapshots to provide up-to-date data. Virtualization makes it easy to move instances between physical servers.
Virtualization also reduces costs and saves up on physical resources. With virtualization, fewer hardware servers are needed in a company or data center, as it enables users to create many operating system instances by running on a single server. This results in lower costs of purchasing, installation, management and maintenance of large amounts of hardware. Virtualization also helps to reduce the risk of overheating physical servers and to improve energy savings.
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In a virtual environment, testing becomes less complicated. Tests do not need to be stopped and restarted from the beginning in the event of a severe mistake. It is easy to restore a previous snapshot and carry on with the test.
Virtualization also leads to faster backups. Virtual servers and virtual machines can both be backed up. To ensure that data is updated, snapshots are automatically taken throughout the day. Additionally, it is easy to migrate virtual machines between each other and redeploy them effectively.
Migration to the cloud is made easier for companies through virtualization. Virtual machines play a part in enabling enterprises to adopt a cloud-based culture. They may be deployed from a data center to form part of a cloud-based infrastructure.
Ultimately, the productivity of staff is raised, as having fewer physical resources to manage and maintain means less time is allocated to these activities. Virtualization also reduces the demands on servers and carries out activities in virtual environments much faster than they would take in physical servers.
Drawbacks
For all the benefits brought on by virtualization, upfront costs may prove to be a stumbling block. The upfront investment in virtualization software and hardware may be expensive enough to price out smaller enterprises from implementation. However, partnering with managed service providers can help neutralize the costs.
A virtualized environment may also be accompanied by a learning curve. The relevant teams need to possess skills or be trained in implementing and managing a virtualized environment. They may need to learn new infrastructures such as hypervisors, application programming interfaces, management tools and more. IT teams also need to be aware of the possibility of dealing with applications that adjust correctly when executed in a virtual environment.
Virtualization also faces various security risks. Data proves to be a valuable target for attacks today. As the use of virtualization software has enterprise data stored on third-party resources, the possibility of facing data breaches increases. The risk of stolen, lost or compromised data rises.
Additionally, quick scalability in virtualized environments proves to be complex. Making sure all requisite storage, security, software and resources are available is a time-consuming and tiresome process. Increased resource usage may also yield additional costs.
Features
Resource isolation
Isolated virtual machines are a result of virtualization. Every virtual machine is capable of having multiple guest users in the form of devices, applications, operating systems or other entities. Since virtual machines offer isolated virtual environments to guest users, their sensitive information is secured. However, these isolated environments do not keep guest users from being interconnected with one another.
Virtualization also enables performance tuning. This involves tuning the properties of the resources in the virtual environment to adjust the performance of a guest.
Emulation
The virtualization layer controls the environment in which guest programs are executed. Additionally, guest programs that need specific features that may be missing in a physical host can also be executed in an environment that emulates the host.
Portability
The guest can be stored in a virtual image and can be moved and run on top of different virtual machines in the context of hardware virtualization. The binary code that represents application components is executable without having to recompile on any implementation of the corresponding virtual machine in virtualization on a programming level.
Security
The power to transparently regulate how guest programs execute makes it possible to deliver a secure and controlled execution environment. Managing a virtual machine provides the ability to not only control but also filter the activities of guest programs. This makes it possible to avert harmful operations from being executed.