OpenVZ (Open Virtuozzo) is an operating-system-level virtualization technology that allows multiple isolated virtual private servers (VPSs), also known as containers, to run on a single physical server.
OpenVZ is widely used by hosting providers to offer VPS services. It is also deployed in corporate environments with large network infrastructures to consolidate servers, optimize resource usage, and distribute computing resources across internal systems.
OpenVZ was developed by SWsoft (later known as Parallels, now part of Virtuozzo) and was first introduced in 2000. In 2005, the project was released as open source, allowing developers around the world to contribute to its development.
Advantages of OpenVZ
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One of OpenVZ’s main strengths is its high performance. Because all containers share the same Linux kernel, virtualization overhead is very low.
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OpenVZ also uses system resources efficiently. CPU, memory, and other resources can be dynamically allocated between containers, helping achieve better hardware utilization.
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Another benefit is ease of management. Containers can be created, configured, and controlled using dedicated tools and control panels, making administration relatively straightforward.
Disadvantages of OpenVZ
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OpenVZ is limited to Linux-based operating systems. It cannot run Windows or other non-Linux systems because all containers share the host’s Linux kernel.
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Isolation is also weaker than in full virtualization platforms. Since all containers rely on the same kernel, a kernel-level vulnerability can potentially affect every VPS on the server.
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OpenVZ is less flexible than hypervisor-based solutions such as KVM. It is not possible to run different operating systems or custom kernels inside containers.
For this reason, OpenVZ is best suited to low-cost VPS hosting, where affordability, simplicity, and efficient resource usage are more important than maximum isolation or performance consistency. Resources such as disk space, RAM, and CPU limits can often be adjusted on the fly through a control panel without rebooting the server.
However, OpenVZ is generally not suitable for highly demanding workloads such as video streaming, online gaming servers, large-scale proxying, mass email delivery, or other resource-intensive applications, where strict performance guarantees and full isolation are required.
Despite these limitations, OpenVZ is still widely used by hosting providers around the world and remains a significant part of the VPS market, alongside more modern solutions such as KVM and VMware-based virtualization.