KVM vs. Hyper-V: What Are the Differences?

Virtualization technology has become integral to modern computing and data center infrastructure. One of the most popular virtualization solutions is KVM (Kernel-based Virtual Machine) and Microsoft’s Hyper-V. Businesses, organizations, and individuals use these solutions to create and manage virtualized environments.

While both KVM and Hyper-V provide benefits and offer live migration options for your business, there are some fundamental differences between the two. These basic differences are essential when deciding which platform is right for you. KVM and Hyper-V have distinct sources, with KVM being built on Linux and Hyper-V being a Microsoft-licensed product running on Windows. Additionally, there are differences in memory allocation, management tools, and storage requirements.

As a virtualization manager, these differences make it necessary for you to explore the two solutions and decide which is best for your organization based on your needs. This blog will provide an overview of the two technologies, outlining their advantages and limitations. Afterward, we will compare the two solutions to help you make an informed decision for your business.

Overview of KVM and Its Limitations

KVM is an open-source hypervisor that enables you to run multiple operating systems and applications on a single physical machine. It has become increasingly popular in recent years due to its ease of use and scalability.

In addition, KVM is an example of a Type-1 hypervisor, meaning that it runs directly on the underlying hardware rather than on a host operating system. This feature makes it more efficient than Type-2 hypervisors, which run on top of a host operating system.

Benefits of KVM

KVM offers several advantages for your business if you want to virtualize your infrastructure. Firstly, it’s an open-source solution, meaning updating and improving this platform is easy. This capability is excellent for you, as it allows for rapid development and customization. Furthermore, KVM is highly efficient and scalable, making it ideal for businesses with significant virtualization needs. In addition, KVM can run multiple operating systems, allowing you to switch between different operating systems easily. Finally, being an open-source platform, it doesn’t attract excessive charges. This advantage makes it a good fit for a startup or low-scale enterprise.

Drawbacks

Despite the many advantages of KVM, there are some limitations to consider. Firstly, KVM is incompatible with some hardware or software, meaning you may need to invest in additional infrastructure. Additionally, KVM can be challenging to set up and manage, meaning that you may need to invest in additional personnel or training to use it effectively. Finally, KVM requires a dedicated server, meaning it can be more expensive to set up than other virtualization solutions.

Overview of Hyper-V and Its Limitations

Hyper-V is a virtualization platform from Microsoft that enables you to create and run multiple operating systems and applications on the same physical hardware. It provides an efficient and cost-effective way to use and manage your hardware resources, enabling you to maximize the return on your investment. Hyper-V also supports high availability, scalability, and flexibility, making it an ideal choice for businesses of all sizes.

Benefits of Hyper-V

Hyper-V offers many advantages. These benefits embed in its sophisticated features. Firstly, Hyper-V can reduce your hardware costs. You no longer need to purchase separate servers for each operating system or application you wish to run. In addition, Hyper-V helps you to make the best use of your hardware resources, enabling you to maximize the return on your investment.

Furthermore, Hyper-V provides high availability through its built-in redundancy, ensuring that your applications and data remain available even during a hardware failure. Moreover, Hyper-V allows you to quickly scale up or down as your needs change, making it easy to accommodate sudden spikes in demand. Finally, Hyper-V enables you to run multiple operating systems on the same physical hardware, allowing you to choose the best solution for your business.

Drawbacks

As with any virtualization platform, Hyper-V has some limitations. For example, it can be challenging to manage and maintain. It may not be suitable for some applications due to its limited support for some hardware and software. Additionally, Hyper-V requires a certain level of expertise, making it unsuitable for those inexperienced with virtualization.

Comparison between KVM and Hyper-V

While it’s clear that both KVM and Hyper-V offer tremendous benefits for your business, it is vital to understand the differences between them. This knowledge will enable you to make the best choice for your business. Before exploring the differences, let’s look at the similarities.

Similarities Between KVM and Hyper-V

Both KVM and Hyper-V offer robust features and a range of options to meet the needs of your business needs. Here are the similarities between the two:

Scalability

The first similarity between KVM and Hyper-V is that they both offer a high level of scalability. KVM relies on the open-source Linux kernel, which allows it to function on various hardware platforms. Hyper-V, on the other hand, is a proprietary solution developed by Microsoft. Still, it can support many virtual machines on a single host. This feature means you can scale your virtualization deployments as your needs expand, allowing you to get the most out of your IT infrastructure.

Live Migration of Virtual Machines

Hyper-V and KVM hypervisors can perform live migrations, allowing you to move an operating Virtual Machine (VM) from one host server to another without interruption. This feature has multiple advantages: it allows the maintenance of hosts without causing downtime. It helps balance the load on the heavily used host.

High Efficiency

Both KVM and Hyper-V offer excellent performance. KVM works on the Linux kernel with an inbuilt ability to be fast and efficient. Hyper-V, meanwhile, is built on the Windows Server operating system and has been optimized to provide a high level of performance. This attribute means that you can expect both solutions to offer the best possible performance for their virtual machines.

Differences Between KVM and Hyper-V

KVM and KVM have their advantages and disadvantages, and it’s essential to understand the differences to make the best decision. Here are some specific differences between them:

Source of Technology

The main difference between Hyper-V and KVM relies on the source of the technology. KVM is an open-source virtualization technology built into Linux, and Hyper-V is from Microsoft and runs on Windows. KVM can work on any x86-based computer with an Intel processor that has activated Virtualization Technology or an AMD processor with the Secure Virtual Machine feature running a Linux kernel.

Microsoft provides Hyper-V in the Windows Server, Windows 10 Pro, and Windows 10 Enterprise. It is worth noting that the free version of Hyper-V Server ends with 2019 version, there is no 2022 version and currently it require fully licensed Windows Server 2022. For one server deployments we can also consider to install VMware Esxi that also have free license (but this option will be sufficient only for very small deployments). However, the base operating system does not restrict the guest operating systems that KVM and Hyper-V can run. While KVM runs on Linux, it can still run Windows virtual machines. Microsoft Hyper-V can still accommodate Linux virtual machines.

Available Management Tools

KVM and Hyper-V are two distinct virtualization technologies that operate on disparate operating systems and necessitate particular management utilities.

Suppose you prefer a graphical user interface for managing KVM. In that case, multiple options exist, such as Cloonix, Morpheus, and Platform9 Managed OpenStack. Alternatively, the command line offers complete control over KVM. Meanwhile, you can use GUI-based tools such as Hyper-V Manager or Windows Admin Center to manage Hyper-V. However, it is possible with the Windows PowerShell command line.

Suppose your IT requires a more robust solution. In that case, Microsoft provides the System Center Virtual Machine Manager (VMM). This enterprise-grade management tool offers scalability and a consolidated view of VM infrastructure but requires a separate license.

KVM and Hyper-V are both highly adaptable in terms of hardware compatibility. KVM can use any storage compatible with Linux, such as direct-attached and network-attached storage (NAS). On the other hand, Hyper-V requires the server message block protocol 3.0 for the virtual machine’s files to be stored on NAS or in a network file share.

Memory Provisioning Options

Hyper-V and KVM provide the capability for varying amounts of memory usage, using uniform and non-uniform memory access. However, when it comes to dynamic memory allocation, there is a difference. Hyper-V is equipped with the ability for dynamic memory allocation, whereas KVM does not offer this feature. Furthermore, KVM enables you to employ memory overprovisioning by running individual VMs as processes. As opposed to devoting specific memory chunks to each VM, the Linux OS distributes memory when a VM requests it. This feature allows you to exceed memory requirements even when physical memory is insufficient. In such scenarios, you can shift some memory pages to swap memory to free up RAM.

Hyper-V has a dynamic memory feature that allows VMs to acquire or free up memory according to their current needs while never surpassing a set limit. This dynamic memory capability enables you to exceed the allocated memory, increasing the number of VMs hosted on one server.

Final Thought

KVM and Hyper-V are great virtualization solutions, offering advantages and disadvantages. KVM is an open-source solution suitable for both Linux and Windows-based environments. It is easy to set up and manage and provides a high degree of flexibility. On the other hand, Hyper-V is a proprietary solution designed explicitly for Windows-based environments. It is a robust solution but is more difficult to set up and manage.

KVM is an excellent choice if you need a robust virtualization solution with a high degree of control and flexibility. Also, it is a reasonable choice if you wish to run multiple operating systems on a single server or to look to build your cloud-based infrastructure. On the other hand, Hyper-V is the ideal choice if you are looking for a reliable and robust virtualization solution tailored to your specific Windows-based environment.

Based on the above, we recommend that you assess your needs when considering a virtualization solution and decide which solution best fits those needs. If a highly flexible solution is needed, KVM is a great choice. In contrast, if a reliable and robust solution tailored to a Windows-based environment is necessary, Hyper-V is the way to go. In either case, both solutions offer a great variety of features and are suitable for various IT environments.

Last but not least, organizations using XEN or KVM-based virtualization need to remember that they are still vulnerable to ransomware attacks and other disasters. As such, a reliable backup and recovery software like Storware can come in handy.