Difference Between OpenVZ and KVM

Web hosting services have evolved throughout the years concerning security, reliability, and storage. We have different hosting technologies used nowadays that offer services based on the requirements of the users. There are traditional hosting services as well for the old school users. With the advancement in technologies, there are various options offered to you based on your requirements. Virtualisation is one such technology used to simplify hosting and provide a secure and reliable environment to your website.

VPS web hosting has become one of the most popular hosting services over the year. It uses virtualisation technology to make sure that it reduces your website’s downtime.

We will try to understand the differences between the two virtualisation techniques, namely OpenVZ and KVM and see which one is the best one for your needs.


Open Virtuozzo or OpenVZ is a container-based, operating system virtualisation technology that was created by Virtuozzo by in 2000 and made open-source in 2005. It establishes multiple, secure, and isolated Linux containers on a physical server (sometimes referred to as virtual private servers).

Each container acts as a standalone server. It reboots independently and has root access, users, IP addresses, configuration files, memory, processes, and every other thing that a server requires to run without any worries. This also ensures the efficient use of resources.

OpenVZ servers can run only on Linux based operating systems like Debian, CentOS, Fedora, and so on.


KVM or Kernel Virtual machine is a Linux kernel module that offers a framework for running third-party tools to provide virtualisation. Being a kernel module, it reuses many functionalities provided by the kernel to complete its operations and purposes.

It supports kernel changes, custom kernels, better privacy, and also the resources are entirely allocated to the respective Virtual Machine (VM).

KVM vs OpenVZ 

OpenVZ is a container-based virtualisation technique, and KVM is a framework that allows third-party tools that provide virtualisation. Which one is better? Here are some factor-based differences that will help you choose the right one for you.

  • Resource allocation and overselling 

OpenVZ does not provide fully guaranteed resources. Instead, it shares the resources with other VPS on the same physical server. Also, there are usability constraints when it comes to the use of resources. It includes memory, bandwidth, CPU and disk space. So there are chances that it can be oversold.

KVM can also be oversold as it is more or less a similar technology like OpenVZ. But, the limitations with KVM are relatively lesser as compared to OpenVZ. Something like, limited kernel usage is a perfect example of it. You can tweak, modify, or use a custom kernel with KVM, unlike OpenVZ.

  • Privacy 

Privacy is a big concern when it comes to your website. OpenVZ cannot be claimed as the one with the highest degree of privacy. You can see the individual processes running on OpenVZ server. Not that it is much of a concern for the user, but privacy-conscious users may want to have a private environment.

On the other hand, KVM supports hard disk encryption. That means, no one can see the files on the file system of your VPS if they do not know your root password. This encryption feature makes KVM the most secure virtualisation technology.

  • Kernel 

The shared kernel is one of the limitations of using OpenVZ VPS. Every user is forced to use the same shared kernel. It does not directly affect the user, but it limits them to use only the Linux-based operating system on their servers.

On the other hand, in KVM, every virtual machine has a dedicated kernel. On the KVM VPS server, the user can do whatever they want to the kernel within the server.

Bottom Line

There are many factors to consider when you choose a VPS Hosting. It is essential because there are many other consequences you might have to face for choosing a wrong hosting, including security issues and threats. Based on the above discussion, we would say that you go for a KVM VPS Web Hosting. It is secure, customizable and carries out all the required operations smoothly. Do let us know your thoughts and what technology your web hosting provider offers to keep your data safe in the comments section below.