What is Virtualization?
Virtualization is a technology that allows a single physical machine to host multiple virtual machines (VMs), each of which behaves like a separate physical machine. Virtualization is used in many different contexts, including data centers, cloud computing, and desktop computing.
There are many different types of virtualization technologies, including:
- Hardware virtualization: Hardware virtualization allows a single physical machine to host multiple VMs, each of which has its own virtualized hardware, such as a CPU, memory, and storage. This allows multiple operating systems and applications to run concurrently on the same physical hardware.
- Operating system (OS) virtualization: OS virtualization allows multiple operating systems to run concurrently on the same physical machine, each in its own isolated environment. This is typically achieved by using containers, which are lightweight virtualization technologies that allow applications to be packaged together with their dependencies and run in isolated environments on a host operating system.
- Desktop virtualization: Desktop virtualization allows users to run a virtual desktop on a physical machine, either on the same machine or remotely. This can be useful for allowing users to access their desktop from different locations or devices, or for running multiple operating systems on the same machine.
Virtualization has many benefits, including:
- Resource utilization: Virtualization allows multiple VMs to share the resources of a single physical machine, which can improve resource utilization and reduce costs.
- Portability: Virtualization allows VMs to be easily moved between physical machines, which can be useful for disaster recovery and other scenarios.
- Isolation: Virtualization allows VMs to be isolated from each other, which can be useful for security and other purposes.
Overall, virtualization is a powerful technology that allows multiple operating systems and applications to run concurrently on the same physical machine, improving resource utilization and portability.
Understanding Hypervisor
A hypervisor, also known as a virtual machine manager (VMM), is software that enables the creation and management of virtual machines (VMs) on a computer. A virtual machine is a software-based emulation of a physical computer, with its own operating system, hardware, and software applications.
Hypervisors allow multiple VMs to run on the same physical hardware, each with its own operating system and applications. This can be useful for a variety of purposes, such as testing new software, isolating applications from each other, and increasing the utilization of physical hardware resources.
Two categories of hypervisors exist:
Type 1 hypervisors, also known as “bare-metal” hypervisors, interact with the underlying physical resources, effectively replacing the traditional operating system. They are most commonly encountered in virtual server scenarios.
Type 2 hypervisors run as an application on top of an existing operating system. They have a performance overhead because they must use the host OS to access and coordinate the underlying hardware resources. They are most commonly used on endpoint devices to run alternative operating systems.
Hardware Virtualization
Hardware virtualization is the process used to build virtual representations of real desktops and operating systems. Essentially, it hides the physical hardware. To give several guest operating systems abstracted hardware so they can more effectively share the physical hardware resources, it uses a virtual machine manager known as a hypervisor. Many advantages come with hardware virtualization, including increased performance and cost savings.
In a conventional physical computing environment, software like an operating system or business application has direct access to the underlying computer hardware and components, such as the processor, memory, storage, some chipsets, and OS driver versions. This created significant configuration issues for software and made it challenging to relocate or reinstall software on new hardware, such as when restoring backups following an error or tragedy.
A hypervisor or virtual machine manager is installed as part of hardware virtualization, creating an abstraction layer between the software and the underlying hardware. Software then uses virtual representations of the computing components, such as virtual processors, rather than actual physical processors, after a hypervisor is in place.
In hardware-assisted virtualization, the virtual machine manager, or hypervisor, receives architectural support from the physical components of the computer. A host computer can run many guest operating systems simultaneously in isolation thanks to the use of hardware and software, preventing potentially hazardous instructions from being directly executed on the host machine. These physical components, which optimize virtualization in a number of ways, are mainly made up of host processors.
Basic Components of Hardware Virtualization
1. The hardware
The actual server parts, including the CPU, RAM, network, and disk drives, are found in the hardware layer, also known as the virtualized host. This is the actual hardware that supports virtualization. All supported guest operating systems need an x86-based machine with one or more CPUs in order to run.
2. The hypervisor
By establishing a virtualization layer between the operating system and the server hardware, the hypervisor enables several instances of one operating system or multiple operating systems to run simultaneously on a single computer. The virtual machines that utilize the host machine’s resources are kept separate from the operating systems and programs that run on top of it.
3. Virtual machines
Virtual machines are software simulations of a hardware computing environment that offer all the features of a real computer. Virtual hardware, a guest operating system, and guest software or applications make up virtual machines themselves.
Famous Hardware Virtualization Products:
1. VMware ESXi
2. Microsoft Hyper-V
3. Xen
Advantages of Virtualization
1. Save money
One physical server becomes several virtual computers when an environment is virtualized. These virtual computers can all be housed on a single physical server, but they can all run various operating systems and applications. Because you can employ fewer physical clients, consolidating the apps into virtualized environments is a more cost-effective strategy that will help you spend much less on servers and save money for your company.
2. Reduce downtime
You can create redundant virtualized environments with extraordinarily high availability since cloning a VM is practically trivial. Virtualization offers an incredibly dependable system with no single point of failure in hardware or software by automatically monitoring VM status and quickly transitioning to backup VMs in the event of an outage. You may effortlessly carry on running your VM from its most recent operational state thanks to these “failover” mechanisms. This ensures that services are always available to customers.
3. Increased efficiency
Physical ecosystems are far more difficult to maintain than virtual ones. Virtualization enables you to configure, monitor, and update all of your VMs from a single machine rather of managing several physical servers that each require unique care. This reduces the amount of time it takes to deploy updates, apply security fixes, and install new software. Your IT crew spends less time worrying about managing physical machines because there is less physical hardware to manage. Your developers appreciate the effectiveness of quickly launching a VM without worrying about including new hardware.
4. Better DevOps Delivery
You can divide a working environment into multiple virtual machines using virtualization. To test an application or complete another activity, any developer can rapidly swap from one VM to another.
It won’t be necessary for developers to request a new PC with the necessary operating system.
5. Save Energy
The majority of people and businesses find virtualization to be an energy-efficient approach. Energy usage rates can be reduced because no local hardware or software alternatives are being used. To increase the total ROI of virtualization, money can be spent on other operational expenses over time rather than the cooling costs of a data center and the operational costs of equipment.
In conclusion, virtualization technology has transformed the way we think about computing, enabling us to achieve greater efficiency, flexibility, and scalability in our IT infrastructure. By leveraging virtualization, businesses and organizations can consolidate their computing resources, reduce hardware costs, and improve their agility in responding to changing needs and demands.