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

Docker container daemon architecture

Containers are a simple and smart answer to the need to run isolated process instances. We can safely affirm that containers are a form of application isolation that works at many levels, such as filesystem, network, resource usage, process, and so on.

As we saw in Chapter 1, Introduction to Container Technology, in the Containers versus virtual machines section, containers also differ from virtual machines because containers share the same kernel with the host, while virtual machines have their own guest OS kernel. From a security point of view, virtual machines provide better isolation from potential attacks, but a virtual machine will usually consume more resources than a container. To spin up a guest OS, we usually need to allocate more RAM, CPU, and storage than the resources needed to start a container.

Back in 2013, the Docker container engine appeared in the container landscape, and it rapidly became very popular.

As we explained...