In IT, a virtual machine (VM) is a virtual emulation of a physical computer system that operates independently within a host system. It behaves and operates like a real computer, complete with its operating system (OS) and software applications.
What Entails a Virtual Machine?
Before we look into how a virtual machine operates, let us understand what encompasses a virtual machine. A virtual machine is made up of:
Host Machine: Also called the host server, it runs a special software called virtual machine monitor (VMM) that holds and manages virtual machines.
Guest Operating System: Every virtual machine within a single host runs on its guest operating system. The guest OS is different from the host operating system.
Virtual Hardware: The VMM presents virtual computer hardware components like CPU containing RAM and storage disks, network components, and more.
These create a virtual machine that is isolated and highly portable in terms of functionality.
Advantages of VMs
Virtual machines are widely employed in cloud computing, software development and testing, application deployment, server consolidation, and desktop virtualization. The main benefits provided by VMs include:
Isolation: VMs are isolated from each other and the processes running in one VM cannot coincide with the resources or data of another VM. Proper authorization and authentication are required to enable two VMs to access each other. The isolation aspect provides an additional layer of security
Portability: VMs are portable and can be transferred or replicated with ease on a different host or cloud environment.
Flexibility and Scalability: VMs are flexible and scalable to meet the ever-dynamic business requirements. IT resources can be scaled up or down and migrated as frequently as possible without service disruption or downtime.
Swift Recovery: VMs enable the isolation of potential system issues and provide quick recovery capabilities. Both DevOps and IT support teams use VMs to mitigate the repercussions of system failures, application bugs, and potential security incidents.
VMs enhance online and cloud security, optimize IT infrastructure, enhance agility in service provision, and are cost-effective in the long run.
Virtual Machines Use in IT
VMs, in DevOps and IT support, provide a versatile platform for effectively managing software development, troubleshooting issues, and providing speedy assistance to end-users.
VMs are used in:
Testing Environment and Troubleshooting
By providing a safe environment for testing and pseudo-deploying applications developed, developers can troubleshoot any issues and diagnose them in real-time. The environment can be replicated to encompass the various stages in the application development lifecycle due to its flexibility and scalability nature.
These environments can also be used to validate software updates, and patches ensuring compatibility and minimizing the risk of failures.
Disaster Recovery and Remote Support
IT support personnel utilize VMs to roll out disaster recovery strategies to ensure data protection and minimize unforeseen downtime or disruptions.
VMs enable continuous, real-time IT support by accessing and diagnosing systems over the virtual network subsequently enhancing customer satisfaction.
Capacity Planning and Testing
Through VMs, capacity planning, and testing activities evaluate resource utilization and monitor performance metrics to optimize IT systems performance. VM capacity planning and testing identifies infrastructure choke-points and future growth capabilities, for optimal resource allocation.
Limitations of Virtual Machine
VMs, despite their versatility and powerful nature, in handling a network of operating systems, are not without some limitations.
Host Hardware Limitations
VMs are hosted on a single physical unit, and it has to be state-of-the-art. The host machine ought to have powerful CPU cores and be fixed with several RAM units for efficiency. If the host machine possesses outdated components, there will be reduced functionality.
Network Configuration Challenges
Similar to physical networking configurations, misconfiguring a VM network will impair performance and/or lead to security vulnerabilities.
Licensing Costs
The legal circumstances surrounding the establishment of VMs as well as regulations and policies need to be carefully considered before deploying and managing virtual environments.