Book Image

Podman for DevOps

By : Alessandro Arrichiello, Gianni Salinetti
Book Image

Podman for DevOps

By: Alessandro Arrichiello, Gianni Salinetti

Overview of this book

As containers have become the new de facto standard for packaging applications and their dependencies, understanding how to implement, build, and manage them is now an essential skill for developers, system administrators, and SRE/operations teams. Podman and its companion tools Buildah and Skopeo make a great toolset to boost the development, execution, and management of containerized applications. Starting with the basic concepts of containerization and its underlying technology, this book will help you get your first container up and running with Podman. You'll explore the complete toolkit and go over the development of new containers, their lifecycle management, troubleshooting, and security aspects. Together with Podman, the book illustrates Buildah and Skopeo to complete the tools ecosystem and cover the complete workflow for building, releasing, and managing optimized container images. Podman for DevOps provides a comprehensive view of the full-stack container technology and its relationship with the operating system foundations, along with crucial topics such as networking, monitoring, and integration with systemd, docker-compose, and Kubernetes. By the end of this DevOps book, you'll have developed the skills needed to build and package your applications inside containers as well as to deploy, manage, and integrate them with system services.
Table of Contents (19 chapters)
1
Section 1: From Theory to Practice: Running Containers with Podman
7
Section 2: Building Containers from Scratch with Buildah
12
Section 3: Managing and Integrating Containers Securely

Managing container images

In this section, we will see how to find and pull (download) an image in the local system, as well as inspect its contents. When a container is created and run for the first time, Podman takes care of pulling the related image automatically. However, being able to pull and inspect images in advance gives some valuable advantages, the first being that a container executes faster when images are already available in the machine's local store.

As we stated in the previous chapters, containers are a way to isolate processes in a sandboxed environment with separate namespaces and resource allocation.

The filesystem mounted in the container is provided by the OCI image described in Chapter 2, Comparing Podman and Docker .

OCI images are stored and distributed by specialized services called container registries. A container registry stores images and metadata and exposes simple REpresentational State Transfer (REST) application programming interface...