Podman: Fundamentals

Container Management#

Creating and Running Containers#

• Running a container interactively:

  podman run -it --rm alpine sh

• Running a detached container:

  podman run -d -p 8080:80 nginx

• Assigning a name to a container:

  podman run --name mycontainer -d nginx

Stopping and Restarting Containers#

• Listing running containers:

  podman ps

• Stopping a container:

  podman stop <container_id>

• Restarting a stopped container:

  podman start <container_id>

• Removing a container:

  podman rm <container_id>

Image Management#

Pulling and Pushing Images#

• Pull an image from a registry:

  podman pull nginx

• List downloaded images:

  podman images

• Remove an image:

  podman rmi nginx

• Push an image to a registry:

  podman push myimage:latest docker.io/myrepo/myimage:latest

Building Images with Podman#

• Writing a simple Dockerfile:

  FROM alpine
  CMD ["echo", "Hello, Podman!"]

• Building an image:

  podman build -t myimage .

• Running the newly built image:

  podman run myimage

Managing Container Images with Podman#

Tagging and Inspecting Images#

• Tagging an image:

  podman tag myimage:latest myrepo/myimage:v1

• Inspecting an image:

  podman inspect myimage

Saving and Loading Images#

• Saving an image as a tar file:

  podman save -o myimage.tar myimage:latest

• Loading an image from a tar file:

  podman load -i myimage.tar

Container Lifecycle Management#

Container States#

• Running: Container is active and executing.
• Stopped: Container has been stopped.
• Exited: Container has completed execution.
• Paused: Container is temporarily halted but still exists.
• Created: Container has been defined but not started.

Managing Persistent Containers#

• Restarting a container on boot using systemd:

  podman generate systemd --new --files --name mycontainer

• Viewing container logs:

  podman logs mycontainer

• Checking container status:

  podman ps -a

Hands-on Exercises#

1. Create and Manage a Web Server Container#

podman run -d --name webserver -p 8080:80 nginx
podman ps
podman logs webserver

2. Build and Run a Custom Container Image#

echo -e "FROM alpine\nCMD [\"echo\", \"Hello Podman!\"]" > Dockerfile
podman build -t hello-podman .
podman run hello-podman

3. Push an Image to a Registry#

podman tag hello-podman docker.io/myrepo/hello-podman:v1
podman push docker.io/myrepo/hello-podman:v1

Summary & Next Steps#

Key Takeaways#

• Podman provides a powerful way to create, run, and manage containers.
• Images can be pulled, built, and pushed to registries.
• Container lifecycle management ensures smooth operation and debugging.

Next Module: Advanced Podman Concepts#

In the next module, we will explore Podman Pods, container networking, persistent storage, and health checks.