Containerization has revolutionized the way software applications are developed, deployed, and managed. Docker has been the go-to containerization tool for many years, but recently, a new player has emerged in the field – Podman. In this article, we will compare Podman and Docker briefly.
Architecture
Docker and Podman differ significantly in their architecture. Docker utilizes a client-server architecture, where the Docker daemon runs as a separate entity, handling container operations.
In contrast, Podman follows a daemon-less or daemon-free architecture. It relies on the user’s session to execute containers, eliminating the need for a central daemon. This approach allows Podman to integrate more seamlessly with the existing Linux infrastructure.
Security
Security is a critical concern when it comes to containerization. Docker relies on a privileged daemon, which grants it elevated access to the host system. While Docker has implemented several security measures, the privileged nature of its daemon has raised concerns.
On the other hand, Podman operates in the user space and executes containers as regular processes. By leveraging Linux namespaces and seccomp, Podman provides strong isolation and security, reducing the attack surface.
Rootless Containers
One significant advantage of Podman over Docker is its ability to run containers as a non-root user. Docker requires root privileges to function correctly, which can be a security risk.
With Podman, individual users can create and manage containers without requiring elevated privileges. This feature enhances security and allows for a more fine-grained control of container operations.
Image Management
Both Podman and Docker use the same container image format, making them compatible with each other. But the tools differ in how they handle image management. Docker relies on a centralized image registry, Docker Hub, as the default repository for sharing and distributing container images.
Podman, on the other hand, allows users to pull and push images from any container registry without the need for a central authority. This decentralized approach gives users more flexibility in choosing where to store and retrieve images.
Container Orchestration
Docker has a built-in container orchestration solution called Docker Swarm, which allows users to manage multiple containers and distribute workloads across a cluster of hosts. Docker Swarm is relatively lightweight compared to other orchestration tools.
On the contrary, Podman does not provide a native container orchestration solution like Docker Swarm or Kubernetes. But Podman can seamlessly integrate with existing orchestration frameworks, including Kubernetes, enabling users to leverage the power of these established tools.
Conclusion
The choice between Podman and Docker depends on your specific requirements, preferences, and the level of community support you seek.