Podman vs Docker vs Pacman :)

Game over for Docker?

Well, hello there.

Docker has become synonymous for running containers, a little like (in the UK anyway!) you would say “I am going to hoover the carpet”. Hoover is a brand of course, and just a vacuum cleaner in reality.

So, this Podman thing? what makes it different and why should I care?

Docker has become synonymous with containers, as it played a significant role in pioneering containerization technology. This technology has revolutionized the way we package our code, libraries, and runtime, simplifying the deployment and management of applications.

Docker consists of various components, including the Docker file, which contains instructions to build images. Images, in turn, encompass everything necessary to run a container. The Docker engine, a key part of Docker, is responsible for running containers in the background.

The Docker architecture operates on a client-server approach. Users interact with the Docker CLI or the Docker desktop application, which sends commands to a background daemon process. This daemon process handles tasks like running containers, working with registries, and pulling down images. However, there are limitations to the Docker Daemon. Organizations without root access or sudo privileges will need to request permission to run Docker commands. Moreover, running the Docker daemon on systems with root access may present security vulnerabilities.

This is where Podman comes into play. Podman, like Docker, is a container engine that focuses on security. However, it diverges from Docker's architecture by eliminating the need for a central daemon. Instead, users interact directly with the client. When creating new containers, Podman forks itself, with the child process becoming the container. This daemon-less architecture allows Podman to run in a rootless fashion by default, enhancing security.

Podman shares many components with Docker, including images and containers, as well as adherence to the Open Container Initiative (OCI) standards. Additionally, Podman introduces the concept of pods, which enables multiple tightly-coupled containers to share the same volume and network. With Podman, these pod manifests and YAML files can be deployed in a Kubernetes cluster, simplifying the transition to Kubernetes.

While Docker requires the Docker daemon and supports Docker-specific features like Swarm for container orchestration, Podman offers comparable functionalities. For multi-container applications, both Docker and Podman have their respective compose features. Whether you prefer a visual interface or command-line interaction, both Docker and Podman provide desktop applications and CLIs for different operating systems.

To determine which container engine is best suited for your needs, consider the following factors. Docker, being the industry standard, boasts a larger user community, extensive documentation, and abundant resources for beginners. Docker also has native features like Docker Swarm that are absent in Podman. On the other hand, if you prioritize running containers in a rootless fashion, focusing on security, or transitioning to Kubernetes, Podman may be the better choice.

Ultimately, both Docker and Podman are exceptional container engines.

I don’t think it is game over for Docker however, some of the key features of Podman are indeed very appealing!