A hypervisor, also known as a virtual machine monitor (VMM), is a type of software used to create and run virtual machines. There are two main types of hypervisors with a wide range of use cases, including consolidating servers by moving workloads to virtual machines, creating isolated environments for testing and development, and facilitating remote desktop access. This article is an introduction to hypervisor technology, how it works, and the benefits and drawbacks of using it.
What Is a Hypervisor and How Does it Work?
Traditional computers run one operating system, or OS, at a time. This makes them more stable, as the hardware receives only limited processing requests, but it’s also limiting. A hypervisor is a type of software that enables multiple instances of operating systems to run on the same physical resources. These multiple instances are called virtual machines.
Hypervisors work by separating the host machine’s OS, software, and applications from the underlying physical hardware and resources, allowing for multiple “guest” operating systems to share the same hardware resources without being in connection or communication with one another.
Each guest OS operates as if it has all the host’s resources to itself. The hypervisor manages available resources so that each guest OS has reliable access to enough processing power, memory, and storage to function properly. It allocates resources according to the requirements of the guest system and the applications running on it, but also according to the virtual environment’s administrator settings.
The hypervisor also ensures that activities in one virtual environment do not affect others, maintaining the privacy, independence, and security of each virtual machine.
Benefits of Hypervisors
Cloud computing has driven a rapid growth in the hypervisor market. The following are some of the benefits of hypervisors.
- Cost-Effectiveness. Companies can save resources using hypervisors by reducing the need for hardware and physical storage space. Instead of running different applications on separate machines, a hypervisor allows for multiple virtual machines to operate on a single hardware platform, leading to significant cost savings.
- Efficiency and Scalability. Hypervisors increase efficiency and scalability by facilitating the migration of virtual machines and digital assets and operations between different host machines. This feature is especially beneficial in cloud computing, where resources need to be scaled up or down based on demand.
- Host Isolation. Hypervisors allow for the complete isolation of each virtual machine. This capability is crucial because if one virtual machine fails or gets compromised by outside malicious actors, the others remain unaffected, ensuring business continuity.
Types of Hypervisors
There are two ways to deploy hypervisor technology. The choice depends on the location of the hypervisors relative to the hardware resources and OS.
Type 1 Hypervisors
Type 1 hypervisors, also known as native or bare-metal hypervisors, run directly on the host machine’s hardware. This enables them to control the hardware and effectively manage guest systems. They allow for high performance and are often used in enterprise environments where efficiency and resource optimization is paramount.
Type 2 Hypervisors
Type 2 hypervisors, or hosted hypervisors, run atop a conventional OS just like other computer software. While less efficient than Type 1, they’re easier to set up and manage, making them more suitable for smaller environments or individual use.
Hypervisor Use Cases
There are multiple scenarios for using hypervisors. Here are a few of the most popular.
Hypervisors play a critical role in server consolidation, allowing companies to reduce their physical server count by moving workloads to virtual machines. This leads to fewer costs, energy consumption, and cooling needs. They can also improve performance and reduce necessary labor.
Testing and Development
Developers can use hypervisors to create isolated virtual environments for testing and development without needing additional hardware resources. By creating a virtual environment on the primary host, developers can simulate various conditions to test their latest software or applications at a fraction of the cost.
Virtual Desktop Infrastructure
Hypervisors support Virtual Desktop Infrastructure (VDI), allowing employees to access their work desktops remotely without the need to install and maintain a separate device per employee.
What are Cloud Hypervisors?
The backbone of modern cloud computing, cloud hypervisors enable the creation of multiple virtual machines, similar to multi-tenant architecture, on which cloud services run over an internet connection. The technology provides the scalability and flexibility that cloud services require to meet varying customer demands without the need to acquire and maintain numerous physical servers.
Cloud hypervisors are essential for businesses of all sizes, from small startups to large enterprises, as they offer an easy way to build and manage cloud-based applications and services for clients and staff.
Additionally, cloud hypervisors support the automated management of resources, reducing operational costs by allowing businesses to scale up or down based on demand. By using hypervisors to build their cloud environments, businesses can focus on their core business operations while enjoying the benefits of a flexible and secure cloud computing experience.
Security Considerations with Hypervisors
As with all connected technologies, hypervisors are subject to security risks. Here are a few of the main concerns.
Vulnerability to Attacks
As the controlling element of a virtual environment, a hypervisor can become a target for cyberattacks. It’s essential to keep all software updated with the latest security patches.
If a hypervisor fails to maintain isolation between virtual machines, it could lead to data leaks or breaches.
Without proper access control and administration, a hypervisor can be manipulated to gain unauthorized access to virtual machines connected to the same host.
Hypervisors vs. Containers
While both hypervisors and containers enable software to run reliably when moved from one computing environment to another, they function differently.
Hypervisors virtualize host hardware to run multiple operating systems, while containers virtualize the OS to run multiple instances of the same application. The main difference between hypervisors and containers is that hypervisors are more isolated from each other, while containers are more lightweight and portable.
Generally, hypervisors tend to be best suited for larger applications that require more resources, while containers are best used for smaller applications or microservices. Containers also have the advantage of providing greater flexibility, allowing applications to be moved quickly and easily between different environments.
When choosing between a hypervisor and a container, consider the size and scope of the application as well as the security requirements.
Bottom Line: Hypervisors
Hypervisors play a vital role in virtualization, providing cost savings, flexibility, and scalability. Enterprises are increasingly turning to hypervisor technology to help create, manage, and use virtual machines for a growing range of uses. As they continue to evolve, they’re becoming more efficient and secure, with greater compatibility, and are moving toward lightweight solutions designed for specific tasks and work across different hardware platforms.
Read next: What is Multi-Tenant Architecture?