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

Monitoring containers with health checks

Starting with version 1.2, Podman supports the option to add a health check to containers. We will go in depth in this section into these health checks and how to use them.

A health check is a Podman feature that can help determine the health or readiness of the process running in a container. It could be as simple as checking that the container's process is running but also more sophisticated, such as verifying that both the container and its applications are responsive using, for example, network connections.

A health check is made up of five core components. The first is the main element that will instruct Podman on the particular check to execute; the others are used for configuring the schedule of the health check. Let's see these elements in detail:

  • Command: This is the command that Podman will execute inside the target container. The health of the container and its process will be determined through the wait...