Containers have transformed how applications are built, deployed, and managed. They provide light, portable, and scalable options for developers and IT professionals. Docker has been the dominant player in the container space, but over the past few years, Podman has become a solid contender. Both tools support the management of containerized applications, but they differ in architecture, security, and usage.
In this blog, we will compare Docker vs. Podman in depth, assisting you in deciding which tool is right for you.
Overview of Docker and Podman
What is Docker?
Docker is an open-source container platform that enables developers to automate application deployment within lightweight, portable containers. Docker comprises a few components, namely the Docker Engine, CLI (Command Line Interface), and Docker Hub.
What is Podman?
Podman (short for Pod Manager) is an open-source container management tool from Red Hat. It is a daemonless, rootless, and more secure version of Docker, providing the same functionality but with a different method
Main Differences Between Podman and Docker
Daemon vs. Daemonless Architecture
A major difference between Docker and Podman is their architecture.
- Docker is a daemon, which means it has a continuously running background service (dockerd) that runs containers. This single point of failure can be problematic for security and reliability.
- Podman is rootless, where every container gets executed as the child process of the user and has lower possibilities of security exploitation, enhancing the system's overall stability.
Rootless Running and Security
Security in the context of containerized operations is a predominant concern. Podman supports the option of a rootless execution of containers by providing them root-less run conditions.
- Docker by default involves running with a root requirement to run, thereby representing a source of security if abused.
- Podman supports running containers without root privileges, lowering attack surfaces and making it the go-to choice for security-oriented environments.
OCI Standards Compatibility
Both Docker and Podman adhere to the Open Container Initiative (OCI) standards, which provide compatibility with container images.
- Docker images can be utilized by Podman, and vice versa, without the need for modification.
- Podman supports the same Docker CLI commands, which makes it easier for developers to migrate.
Pod Management
- Podman brings pod management, as in Kubernetes, to allow several containers to share a common network namespace.
- There is no built-in support for pods in Docker. It needs Kubernetes for such an operation.
- Podman has built-in support for pods and is an excellent choice for developers of Kubernetes.
System Resource Usage
- Podman doesn't depend on a background daemon. As a result, it uses fewer system resources than Docker.
- Docker daemon runs permanently, even without containers running, causing increased CPU and memory consumption.
- Podman executes processes on demand, making it lighter and more efficient.
Volume and Networking Management
- Docker possesses a mature network and volume management system, and it is simple to create and manage communication among containers.
- Podman needs to be configured differently to manage networking, particularly for advanced multi-container applications.
When to Use Docker or Podman?
Use Docker when:
- You require an end-to-end solution for containerization.
- You are using Docker Composer extensively.
- You need strong networking features out of the box.
- You want ease of use above security considerations.
Use Podman when:
- Security is your utmost priority (rootless execution).
- You desire a daemonless, minimal container runtime.
- You are operating with Kubernetes and require built-in pod support.
- You are containerizing on a multi-user system and need enhanced process isolation.
Conclusion
Both Podman and Docker are robust container management solutions, but each has its differences that suit various use cases. Docker continues to be a favorite due to its ease of use, and Podman is best when security and light execution are concerns.
For users who want a classic and straightforward container solution, Docker still holds good. But when security, performance, and Kubernetes integration are paramount, Podman is an ideal replacement.
Finally, the decision between Podman vs. Docker lies in your own requirements and priorities. Knowing their distinctions can guide you in choosing the most suitable tool for your containerized workloads.