OpenVZ vs. Docker Best Guide
OpenVZ vs. Docker: Comprehensive Comparison
In the modern world of containerization and virtualization, the two most spoken-about technologies are OpenVZ and Docker.
Although they work to make applications more manageable by optimizing the resources, the way to do it differs,
and so is the target usage scenario. In this article, we will discuss the features, advantages, and disadvantages of
both OpenVZ and Docker, and where exactly one should use them.
We will also solve all the typically asked questions in the full-fledged FAQ section.
Understanding OpenVZ and Docker
What is OpenVZ?
OpenVZ is considered a kind of operating system virtualization whereby one physical server hosts
multiple isolated Linux containers or Virtual Private Servers, popularly known as VPS.
To put it differently, several containers run on one physical server; all share the same kernel but
run in their own user space, hence enabling efficient usage and management.
OpenVZ found a wide application in the hosting environment when there is an urgent need to create lightweight virtual environments.
What is Docker?
Where Docker differs is that it’s a light container runtime environment used for the automation of
application deployment, scaling, and management. Different from the fully virtualized system,
Docker containers would implicitly use the host OS kernel but maintain isolated user spaces.
Hence, since its creation and packaging of applications is very fast and effective, it has favored microservices,
continuous integrations, and continuous deployments.
Key comparison areas
1. Architecture
OpenVZ: OpenVZ operates in carving several containers using the very same kernel. Each container acts like an independent virtual server with its own file system, processes, and network interfaces. With no extra overhead in running separate kernels, this architecture is really high performing.
Docker: Similar to Kubernetes, Docker works on the shared kernel architecture; however, it packages the application with its libraries, dependencies, and everything else needed to run that application. In fact, that makes Docker containers portable and consistent, whether in a development or production environment.
2. Performance
OpenVZ: This allows for high performance and low overhead in that all the containers will share the host OS kernel. This will be in enabling efficient use of resources and to run numerous light-weight surroundings on one server. However, since all containers will be sharing the kernel, a kernel crash in one may affect all other containers.
Docker: One would say that containers in Docker are performant and not really heavy. However, if we consider an extra layer Docker introduces in application packaging-that is, images with the Docker engine-it will be more overhead opposed to the raw OpenVZ. In most cases, though, it’s negligible for modern applications.
3. Segregating and Securing
OpenVZ: OpenVZ can provide the major amount of isolation. In this case, every container runs independently. But because these share the very same kernel, there is a risk that a threat could propagate in the kernel layer if a used vulnerability may affect all containers.
Docker: Although Docker allowed great isolation due to the idea of containerization, just like OpenVZ, actually it shared the host kernel. In Docker, security features include user namespaces, integrated SELinux, which helps reduce the attack vectors. That said, Docker’s focus on application delivery means that users need to pay attention to security best practices with respect to container configurations.
4. Use Cases
OpenVZ:
Web Hosting: OpenVZ finds its application in web hosting when it involves shared hosting, meaning that many users are sitting on one physical server.
Virtual Server/Virtual Private Server: This is used as an anchor because of low overheads with good resource allocation in creating a VPS solution.
Dev Environments: OpenVZ can be used to create virtual private development environments to test different configurations of an application.
Docker:
Microservices Architecture: Docker provides an ideal environment for deploying microservices; hence, teams can develop faster, ship, and then run applications with reliability.
Continuous Integration / Continuous Deployment: Yes, through consistent environments, Docker does alleviate the pain of a developer concerning CI/CD.
Large Applications: Docker is for big applications, huge service management, putting into consideration some of its orchestration tools such as Kubernetes.
5. Ease of use / Learning Curve
OpenVZ: The OpenVZ setup is pretty smooth, especially if someone is comfortable with Linux; however, the management of the containers requires knowledge regarding the underlying architecture and hence may be a little tough for the beginners.
What the DOCKER Developers refer to is simplicity: ease of use. Command-line, GUI interface-don’t you think that Docker Desktop feels quite friendly to both the green and more professional guys? That easiness in learning will be more than enhanced by the thousands of online resources, tutorials, and community support online.
Conclusion
Either OpenVZ or Docker-it depends on one’s needs. Whether doing low-level virtualization of a number of Linux instances with as small an overhead as possible, OpenVZ may be the way to go. But if speed in application deployment does matter, probably in microservices architecture or at least in continuous integration/continuous deployment, Docker is the boss.
Since both of them have so many shared strengths and weaknesses, knowing them would provide the capability to decide for an application or organization.
1. What is the core difference between OpenVZ and Docker?
OpenVZ is the OS virtualization technology that allows running multiple isolated environments on a physical server, while Docker is a lightweight containerization platform to help one automate the deployment of applications.
2. Does OpenVZ currently support any non-Linux OS?
No, OpenVZ only supports Linux-based operating systems since the virtualization is done using the Linux kernel.
3. Does Docker go to a production environment?
Yes, Docker has seen extensive use in production because it packages applications and their dependencies in a consistent way; hence, deployments are reliable.
4. What is the main advantage of Docker over OpenVZ?
Yes, Docker has a better way of application portability and usability. Yes, Docker does provide fast development and deployment cycles, which are very great in modern application development practices.
5. What about running Docker containers inside of an OpenVZ container?
While it could be technically done, it is discouraged because it may cause some performance problems and managing the containers will be more complicated.
6. What are the possible security implications of using OpenVZ?
This is however a risk to some security exposure in case of exploiting the vulnerabilities due to sharing the same kernel by OpenVZ. Security best practices should therefore be employed to reduce the risks.
7. How does OpenVZ handle networking compared with Docker?
OpenVZ leverages the host networking stack and can assign IP addresses directly to the containers. Docker provides a virtual network layer that allows easy communications between containers while still being isolated.
8. Does one need to know how to develop to use Docker?
While Docker is extremely developer-friendly, it is equally a tool that system administrators and operation teams take advantage of to handle infrastructure and application deployments.
The differences between OpenVZ and Docker will further help one make a better decision regarding their needs and development practices in pursuit of optimal performances with good resource utilization in an environment.