Hypervisor is a specialized software that can be installed on most modern computers. Its primary role is to serve as a foundational layer, upon which you can deploy complete operating systems (OS). After installation, these operating systems exclusively interface with the hypervisor itself, and do not interact directly with the underlying hardware of your computer. This is why such systems are commonly referred to as virtual machines (VMs). As a result, the hypervisor assumes the role of virtual machine monitor (VMM).
Fundamentally, the hypervisor abstracts the virtual machine’s operating system away from the underlying hardware of the server. It acts as an intermediary between them. Therefore, when a program within a virtual machine requires data processing, it directs the processing request to the hypervisor. Subsequently, the hypervisor relays this request to the underlying computer hardware.
What is a Hypervisor?
A hypervisor is a type of software or hardware used to create virtual machines, then run and manage them. It is often referred to as a virtual machine monitor (VMM), which encapsulates the purpose of a hypervisor. A hypervisor allows one host computer to support multiple guest virtual machines (VMs), by sharing its resources. It helps solve the problem of singular operating systems, which are transformed into multiple operating systems. This enables the handling of different workloads and processes, by utilizing the same hardware resources.
Core Components of a Hypervisor
Initially, there are two types of hypervisors, Type-1 and Type-2. Where type-1 directly runs on hardware, and acts as the operating system embedded into the computer’s firmware. Whereas, type-2 hypervisors are installed on top of the existing operating systems, and take the form of another program. Irrespective of the type of hypervisor, each comprises of these three basic components:
● Dispatcher: This component focuses on receiving the instructions sent through the virtual machine. It does not carry out these instructions, but instead, it forwards them to one of the other two modules.
● Allocator: This component manages the amount of system resources that are made available to each virtual machine. If an instruction would require a change in the virtual machine’s (VM) current resource allocation, then the allocator will be invoked to compensate the difference.
● Interpreter: Lastly, this component is a collection of interpreter routines. These routines are executed every time the virtual machine tries to execute a privileged instruction. Each routine acts as a trap, and when the privileged instruction activates a trap, the corresponding routine is executed.
What is the Use of a Hypervisor?
Hypervisors allow more efficient use of a system’s available resources, and provide greater IT versatility, as all VMs are independent of the host. This implies that the VMs can quickly shift between the servers, and work with the one that operates under least stress. Hypervisors help reduce the requirement for physical space, energy consumption, and maintenance that is normally required for servers. In short, hypervisors operate at a server level, load the client’s operating system into VMs, share computer resources, and send requests through API calls.
The Role of Hypervisors in Virtualization
The hypervisor plays a critical role in virtualization, by providing a layer of abstraction between the physical hardware, and the provisioned virtual machines (VMs). It is responsible for allocating and managing resources, providing isolation between the VMs, emulating hardware, supporting live migration, and providing backup and recovery capabilities as well.
A hypervisor lays the foundation of modern virtualization technology, and has revolutionized the way organizations deploy and manage IT infrastructure. With the increasing demand for efficient and scalable computing resources, the importance of the hypervisor is only set to increase in the years to come.
The Benefits of Adopting Hypervisors
There are several benefits to using a hypervisor, as it hosts multiple virtual machines simultaneously. Some additional benefits of a hypervisor are listed below:-
Benefit 1: Efficient Utilization of Computer Hardware
The hypervisor is capable of running multiple virtual machines simultaneously. This allows you to not only accomplish more tasks but also make full use of the available computer hardware.
Benefit 2: Isolation Between Virtual Machines
All virtual machines are completely isolated from one another. The VMs are unaware that they are sharing computer hardware, ensuring that each VM operates independently.
Benefit 3: Enhanced Stability
The hypervisor offers a higher degree of stability due to its VM isolation capabilities. If one virtual machine crashes, it won’t have any impact on the stability of the other VMs or the underlying computer hardware.
Benefit 4: Hardware Platform Independence
Since the provisioned machines are purely virtual, they are not tied to any specific computer hardware. They are linked only to the hypervisor, allowing for easy migration between different computer systems or workloads.
Benefit 5: Rapid Deployment of New VMs
The hypervisor enables quick deployment of new virtual machines. As a VM is essentially software, it can be set up and running within minutes.
What is a Cloud Hypervisor?
As Cloud Computing becomes pervasive, the hypervisor has emerged as an invaluable tool for running virtual machines and driving innovation. Many enterprises are migrating their VMs to the cloud, with the help of hypervisors. Enterprises can reap the benefits of cloud infrastructures, reduce hardware expenses, and increase accessibility and scalability for better Return on Investment (ROI). A cloud hypervisor is the under-pinning of all cloud computing offerings, enabling VMs to run side by side on a single server.
It is the multi-tenancy that powers the economics of most cloud offerings. Hypervisors and the VMs they support provide the portability that enables workloads to be easily migrated between cloud providers, and on-premise servers. Cloud hypervisors help cloud service providers (CSPs) reduce the amount of space servers use, reduce the energy consumed, and maintain efficient management.
Choosing the Right Hypervisor
Selecting a hypervisor for a particular function depends on the size of the company, the criticality of the operations or workload, the capital and operational costs, the existing IT infrastructure, and the IT expertise and skills available. Typically, organizations with virtualization and hybrid cloud, try to adopt type-2 hypervisors that are easy to setup.
On the other hand, when performance is an absolute must for the workload, such as big data or time-sensitive processes, critical transactions are better processed by type-1 hypervisors.
Here are few important considerations for choosing the appropriate hypervisor:-
● Complexity: Is the hypervisor easy to deploy, manage, and troubleshoot? What does the console look like? For organizations that like to be in control of their virtualized environment, there are virtualization management tools available out there. These tools help simplify the use of multiple hypervisors, and other virtualization assets.
● Cost: Enterprises that go for higher levels of virtualization, do not focus much on the budget for licensing, especially when they are non-profit or government entities. When contemplating the virtualization of IT environments, an enterprise needs to duly factor in licensing costs. This will enable them to make an informed decision.
● Ecosystem: Does the hypervisor need to support a variety of hardware, and all the widely used guest Operating Systems (OS)? How does it communicate with, or replace any legacy infrastructure that the organization is stuck with? Does it support all major technologies and apps, such as Microsoft and SAP etc.? Answering questions like these, especially during the planning phase, will save the deploying enterprise a lot of worries in the long run.
Hypervisors play an instrumental role in delivering highly efficient virtualized environments. By adding a whole layer of abstraction over physical hardware, the available resources can be utilized much more efficiently, across a wide range of use cases.
Contact ATSG for highly scalable and reliable Cloud Computing solutions, which employ state of the art hypervisors, and other highly advanced elements of virtualization. Our solutions deliver exceptional scalability, agility and flexibility to deploying enterprises.