Hypervisors are a core technology supporting virtualization and cloud environments. They are the key to optimizing server hardware so it can be used by multiple, independent virtual machines (VMs). Hypervisors are vital and foundational elements of modern, agile, and flexible IT infrastructures.

Bare metal servers provide dedicated, single-tenant hardware hosting, offering high performance, full control, and resource isolation, especially for private clouds and compliance-sensitive workloads.

This article discusses the crucial role of hypervisors in virtualized environments and the multiple functions they perform. We examine the two main types of hypervisors used for virtualization in IT environments and why bare-metal hypervisors provide superior performance compared to hosted hypervisor solutions. Hardware compatibility is a key consideration when selecting a hypervisor, as certain hardware requirements and support limitations can impact performance and feature availability.

The Essential Role of the Hypervisor

The hypervisor is specialized virtualization software or firmware that enables multiple virtual machines to run on a single physical machine. It serves as a control layer between the physical hardware resources and the virtual environment. Hypervisors are a core component of the virtualization technology that supports modern businesses.

A hypervisor enables multiple virtual servers to run on the same physical server. The host operating system’s hardware components provide the processing power to meet the VMs’ requirements. Each VM can run a different operating system and application stack. IT teams can enforce specific security policies across groups of VMs to ensure consistency and safeguard sensitive data assets.

Some hypervisors, such as Kernel-Based Virtual Machine (KVM), are integrated into the Linux kernel, offering high performance and scalability across various workloads. Windows Server includes Hyper-V, a hypervisor built into the operating system, providing integration with Microsoft products and licensing benefits.

Primary hypervisor functions

The hypervisor performs the following essential functions to establish an efficient and manageable virtual environment.

  • Resource allocation and scheduling: The hypervisor allocates physical hardware resources to multiple virtual machines. Each VM receives its allocated CPU, RAM, network bandwidth, and storage resources without interfering with other VMs. Hypervisors ensure efficient resource management in enterprise and cloud environments.
  • VM isolation: Multiple VMs share a server’s underlying physical hardware and must maintain isolation to ensure stability and security. A hypervisor prevents VMs from accessing each other’s memory and ensures faults do not propagate across machines. Data is kept secure by logically separating workloads across the shared physical resources. Isolation is essential for creating multi-tenant environments, such as public cloud environments.
  • Hardware abstraction: The hypervisor presents virtualized hardware resources to the VMs’ operating systems. Abstraction provides hardware independence and enables applications to migrate easily between servers, thereby eliminating vendor lock-in. Teams can upgrade the computing hardware without impacting workloads.
  • Performance optimization: A hypervisor acts as a virtual machine monitor and can dynamically adjust resource allocation to ensure guest operating systems obtain optimal performance. Specific optimization techniques include managing network traffic, CPU scheduling, and storage I/O prioritization. Organizations can maintain high performance while maximizing hardware utilization and controlling spending.
  • Lifecycle management: Hypervisors manage the entire lifecycle of virtual machines. They are responsible for multiple functions that simplify management and support automation, including:
    • Creating virtual machines;
    • Starting and stopping VMs to meet user requirements;
    • Producing snapshots and performing rollbacks;
    • Scaling VMs with dynamic resource allocation.
  • Fault tolerance and availability: Hypervisors enhance resilience by automating processes that ensure the continuous availability of mission-critical applications. Hypervisor activities supporting enhanced resilience include:
    • Performing live migrations between hosts;
    • Ensuring consistent performance with load balancing;
    • Failing over clusters to address major disruptions;
    • Restarting VMs automatically after a host failure.

What are the Two Types of Hypervisors?

Two primary types of hypervisors are utilized to create virtualized environments. The two types are bare metal hypervisors and hosted hypervisors. The main difference between the two hypervisor types is where the hypervisor runs.

Bare metal hypervisors run on dedicated hardware without an underlying operating system. Hosted hypervisors run on top of an operating system in the same way as other applications. Client hypervisors are hosted hypervisors that run within the host operating system, primarily used for end-user testing and software development, and typically exhibit higher latency than bare-metal hypervisors. Let’s take a closer look at these two alternative hypervisor solutions.

Bare metal hypervisor type

A bare-metal hypervisor is installed directly on a server’s physical hardware without a traditional operating system. This type of hypervisor installation provides direct access, allowing the hypervisor to manage the server’s CPU, memory, storage, and network resources. Bare metal hypervisors can also be installed at the firmware level alongside the motherboard’s BIOS.

The hypervisor leverages the hardware resources to establish a virtualization layer that creates and manages virtual machines. Its direct hardware interaction eliminates contention with other applications and enables the hypervisor to deliver high performance across all its VMs.

The key characteristics of bare metal virtualization include:

  • High performance because of direct access to computing resources;
  • Enhanced security and isolation for individual virtual machines;
  • Efficient scalability and flexibility;
  • Efficient resource allocation and low latency;
  • Superior resource efficiency compared to Type 2 hypervisors.

Bare-metal hypervisors are particularly suited for regulated industries due to their enhanced security and control over hardware. They are widely used in high-performance computing (HPC) and big data applications that require maximum hardware performance and low latency. They are ideal for latency-sensitive applications because they do not rely on an underlying operating system that slows performance. Bare-metal hypervisors are crucial for disaster recovery plans, as they enable high availability, fault tolerance, and easy environment replication. They also help deliver reliable and secure virtual desktop infrastructure (VDI) with consistent performance for organizations deploying remote or hybrid work models. Bare-metal hypervisors can be scaled by adding more servers or adjusting configurations, without the limitations of a host OS. Vendors typically provide reliable, centralized management consoles for monitoring and managing large-scale bare-metal hypervisor deployments.

However, the complexity of setup and maintenance for bare metal hypervisors requires specialized skills within IT teams, and the cost of implementation can be high, especially for smaller organizations. Bare-metal hypervisors may have limited hardware compatibility, limiting their use in certain environments. They can also lead to VM sprawl, where more VMs are created than needed, resulting in wasted resources. Despite these challenges, bare-metal hypervisors offer superior performance and security compared to hosted hypervisors.

Cloud computing providers use bare-metal hypervisors to deliver dedicated, secure environments. In regulated industries, keeping data isolated and secure is paramount, and bare-metal virtualization provides that isolation while enabling organizations to run multiple virtual machines on the same physical server. The global bare-metal cloud market was valued at $8.5 billion in 2023 and is projected to reach $19.1 billion by 2028.

The performance, scalability, and security that bare-metal hypervisors offer make them an excellent choice for production workloads in enterprise virtualization environments and data centers. When selecting the best bare-metal hypervisor, organizations should consider high-performance options that offer enhanced security, control, and compliance—especially in regulated industries such as healthcare and finance. Bare-metal hypervisors are often used to build cloud infrastructure and for large server consolidation projects. Teams require a degree of technical skills to manage a bare-metal hypervisor environment successfully and efficiently.

Microsoft Hyper-V and VMware ESXi are two of the top bare-metal hypervisors on the market. Citrix Hypervisor is another leading enterprise solution, offering reliable features, flexible licensing options, and a strong relationship with open-source projects such as Xen Project and XCP-ng, making it suitable for organizations seeking advanced capabilities and scalability.

Hosted hypervisor type

A hosted hypervisor runs on an installed operating system, such as Windows, Linux, or macOS. It is a powerful software application that interacts with hardware through the host OS. The hosted hypervisor does not have direct access to the system’s hardware resources.

The key characteristics of a hosted hypervisor include:

  • Lower performance than bare metal hypervisors;
  • Runs on standard desktop or laptop computers;
  • Hypervisor installation does not require technical expertise.

IT teams and individuals commonly use hosted hypervisors for multiple uses that include:

  • Establishing software testing and development environments;
  • Creating training platforms;
  • Experimenting with multiple operating systems.
  • Building a personal virtualization environment to enhance productivity.

Oracle VM VirtualBox and VMware Workstation are two examples of popular hosted hypervisors

Why Bare-Metal Hypervisors Provide Better Performance

The primary reason bare-metal hypervisors outperform hosted hypervisors is their direct hardware access, which eliminates reliance on the operating system. The following specific technical aspects of bare-metal infrastructure enable it to deliver the high performance required by enterprise environments.

Bare-metal hypervisors have direct hardware access. The lack of a competing operating system gives the hypervisor complete control over resource allocation. This level of control over the underlying hardware provides more predictable performance and faster workload execution.

Eliminating the host operating system layer reduces the software stack, resulting in faster I/O processing and lower latency. Reduced contention with OS functions allows for more efficient resource allocation and improves system utilization.

Improved I/O performance for access to physical resources benefits network and storage operations. Communicating directly with hardware components results in faster disk read/write activity and improves network throughput. These factors are essential for supporting high-traffic web applications, big data processing, and AI/ML workloads.

Bare-metal hypervisors provide enhanced security due to the strong isolation between VMs. The hypervisor presents a reduced attack surface compared to a hosted solution and operating system. A bare-metal virtualized environment is more secure and reliable for business-critical workloads.

Companies establishing enterprise virtual environments benefit from the greater stability of bare-metal hypervisors. Businesses can enjoy advanced features such as automated failover, resource pooling, and high availability clustering to meet production requirements. Bare-metal hypervisors can support large numbers of VMs and integrate with enterprise orchestration tools to meet the scalability and flexibility needs of modern organizations.

Use Cases for Bare Metal Hypervisors

Bare metal hypervisors are the backbone of high-performance virtualization in enterprise and cloud environments, offering unmatched efficiency, security, and scalability. Their ability to run multiple virtual machines directly on the same physical server—without the overhead of a host operating system—makes them the preferred choice for organizations seeking optimal performance and resource allocation.

In data centers, bare-metal hypervisors maximize server hardware utilization by efficiently managing multiple virtual machines on a single physical server. This approach reduces the need for additional hardware, lowers operational costs, and ensures that hardware resources are allocated precisely where they are needed. The result is a highly efficient infrastructure that delivers high performance with minimal overhead, even as workloads scale.

Cloud platforms also rely heavily on bare metal hypervisors to provide dedicated hardware resources to clients. Bare-metal cloud environments offer direct hardware access, enabling users to tailor their virtual machines to specific hardware configurations for consistent performance. This is especially valuable for applications demanding high processing power, low latency, and superior performance, such as real-time analytics, scientific computing, and machine learning workloads.

Virtualized environments, including virtual desktop infrastructure (VDI) and web servers, benefit from the enhanced security and efficient resource management that bare-metal hypervisors provide. By isolating virtual machines and providing dedicated resources, organizations can ensure high availability and reliability for critical applications and services.

In enterprise settings, bare metal hypervisors enable IT teams to run multiple operating systems and applications on the same physical server, supporting diverse departmental needs while maintaining strict control over resource allocation. This flexibility allows businesses to optimize their IT infrastructure, reduce costs, and improve operational efficiency. Advanced management tools and features—such as dynamic resource allocation, automated failover, and high-availability clustering—further enhance the value of bare-metal virtualization in these environments.

Security is another key use case, particularly for industries handling sensitive data, such as finance, healthcare, and government. Bare metal hypervisors provide reliable isolation between virtual machines, minimizing the risk of unauthorized access and ensuring compliance with stringent data protection requirements.

Conclusion

Customers need a hypervisor to create a virtualized environment. A company’s or an individual’s use case should influence the type of hypervisor they choose to establish a virtual infrastructure. Businesses planning to use the environment for production workloads should strongly consider a solution built around a bare-metal hypervisor running directly on powerful hardware. Hosted hypervisors should typically be used for testing and development.

Atlantic.Net provides its customers with a full range of bare-metal and dedicated servers that can be customized to meet your business requirements with specific hardware configurations. You can choose the operating system and hypervisor that best address your team’s needs and technical skill level.

Contact our team to learn more about how we can provide the foundation for a productive virtualized environment.