PODMAN

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1.Introduction

Podman: The Modern Container Management Tool.

What is Podman?

Podman (short for Pod Manager) is an open-source container management tool designed as an alternative to Docker. Unlike Docker, Podman is daemonless, meaning it does not rely on a background service to manage containers. It provides a secure way to run, manage, and deploy containers and pods.

Why Use Podman?

Podman offers several advantages over Docker:

Daemonless Architecture – No root privileges required.
Rootless Containers – Improves security by allowing non-root users to manage containers.
OCI Compatibility – Works with Open Container Initiative (OCI) images.
Docker CLI Compatibility – Most Docker commands work with Podman.
Kubernetes Integration – Easily generates Kubernetes YAML files.

2.Installation of Podman

Podman is available for Linux, macOS, and Windows. Below are the installation steps for different operating systems:

For Ubuntu/Debian

sudo apt update

sudo apt install podman -y

sudo apt update

sudo apt install podman -y

For CentOS/RHEL

sudo yum install -y podman

1	sudo yum install -y podman

For macOS (Using Homebrew)

brew install podman

1	brew install podman

For Windows (Using Winget)

link for download podman: https://podman-desktop.io/downloads/windows

After installation, verify Podman by running:

podman –version

1	podman –version

3.Running Your First Podman Container

Podman follows a similar command structure to Docker. To pull and run a basic container:

podman run hello-world

1	podman run hello-world

To run an NGINX container:

podman run -d -p 8080:80 nginx

1	podman run -d -p 8080:80 nginx

Now, visit http://localhost:8080 to see the running NGINX server.

4.Managing Containers with Podman Command:

Listing Containers

Running containers:

podman ps

podman ps

All containers (including stopped ones):

podman ps -a

1	podman ps -a

Stopping and Removing Containers

podman stop <container_id>

1	podman stop <container_id>

podman rm <container_id>

1	podman rm <container_id>

Removing an Image

podman rmi <image_id>

1	podman rmi <image_id>

Checking System Information

podman info

1	podman info

5.Podman vs Docker: Key Differences

Feature	Podman	Docker
Daemonless	Yes	No
Rootless Mode	Yes	No
Uses OCI Images	Yes	Yes
CLI Compatible	Yes	Yes
Pod Support	Yes	No

You can alias Podman to replace Docker commands: alias docker=podman

6.Working with Pods in Podman

Pods in Podman function similarly to Kubernetes pods, allowing multiple containers to share networking and resources.

Creating a Pod

podman pod create --name mypod -p 8080:80

1	podman pod create --name mypod -p 8080:80

Running a Container Inside a Pod

podman run -dt --pod mypod nginx

1	podman run -dt --pod mypod nginx

Listing Pods

podman pod ps

1	podman pod ps

Inspecting a Pod

podman pod inspect mypod

1	podman pod inspect mypod

7.Building and Running Custom Images with Podman

Step 1: Create a Dockerfile.

FROM ubuntu:latest

RUN apt update && apt install -y nginx

CMD ["nginx", "-g", "daemon off;"]

FROM ubuntu:latest

RUN apt update && apt install -y nginx

CMD ["nginx", "-g", "daemon off;"]

Step 2: Build the Image with Podman

podman build -t my-nginx .

1	podman build -t my-nginx .

Step 3: Run the Custom Container

podman run -d -p 8080:80 my-nginx

1	podman run -d -p 8080:80 my-nginx

8.Podman and Kubernetes Integration

Podman allows easy conversion of container configurations into Kubernetes YAML manifests.

Generating a Kubernetes YAML File

podman generate kube mypod > mypod.yaml

1	podman generate kube mypod > mypod.yaml

Applying YAML in Kubernetes

kubectl apply -f mypod.yaml

1	kubectl apply -f mypod.yaml

9.Running Podman as a Systemd Service

Podman integrates with systemd for automated container management.

Generating a systemd Service for a Podman Container

podman generate systemd --new --files --name my-nginx

1	podman generate systemd --new --files --name my-nginx

Enabling and Starting the Service

systemctl --user enable container-mypod

systemctl --user start container-mypod

systemctl --user enable container-mypod

systemctl --user start container-mypod

Basic Podman Commands
Command	Description
podman –version	Check the installed Podman version
podman info	Display system information about Podman
podman –help	Show help for Podman commands

Working with Containers
Command	Description
podman pull <image>	Pull an image from a container registry
podman images	View all available images
podman run <image>	Run a container from an image
podman run -d <image>	Run a container in detached mode
podman run -it <image> bash	Run a container interactively with a shell
podman start <container_id>	Start a stopped container
podman stop <container_id>	Stop a running container
podman restart <container_id>	Restart a container

Basic Container Commands
Command	Description
podman rm <container_id>	Remove a container
podman ps	List running containers
podman inspect <container_id>	View container details
podman logs <container_id>	View container logs
podman exec -it <container_id> /bin/bash	Access a running container’s shell
podman stats <container_id>	Monitor a container’s resource usage

Working with Images
Command	Description
podman search <image>	Search for an image in a registry
podman pull <image>	Download an image from a registry
podman images	List all downloaded images
podman rmi <image>	Remove an image
podman tag <image> <new_image>	Tag an image with a new name
podman history <image>	Show details about an image

Building and Managing Custom Images
Command	Description
podman build -t <image> .	Build an image from a Dockerfile
podman save <image> > <image>.tar	Save an image as a tar file
podman load -i <image>.tar	Import an image from a tar file
podman push <image>	Push an image to a remote registry

Networking and Ports
Command	Description
podman network ls	List all available networks
podman network inspect <network>	View network details
podman network create <network_name>	Create a custom network
podman network rm <network_name>	Remove a network
podman run -p <host_port>:<container_port> <image>	Map ports between host and container

Working with Pods
Command	Description
podman pod ls	List all running pods
podman pod inspect <pod_name>	Show pod details
podman pod start <pod_name>	Start a stopped pod
podman pod stop <pod_name>	Stop a running pod
podman pod rm <pod_name>	Remove a pod

Podman and Kubernetes
Command	Description
podman generate kube <container/pod>	Generate a Kubernetes YAML from Podman
podman kube play <kube>.yaml	Deploy a Kubernetes YAML in Podman

Systemd and Automation
Command	Description
podman generate systemd –name <container>	Generate a systemd service for a container
podman user start container <container>	Start the systemd-managed container
podman user status container <container>	Check the status of the container service

Volumes and Persistent Storage
Command	Description
podman volume create <volume_name>	Create a new volume
podman volume ls	List all volumes
podman volume inspect <volume_name>	Show details about a volume
podman run -v <volume_name>:/path/in/container <image>	Attach a volume to a container

Security and Rootless Mode
Command	Description
podman unshare ls	Open a shell in a user namespace (listing the directory as rootless user)
podman run –userns=keep-id <image>	Run a container with the same user ID as the host

10. Conculsion

Podman is a secure, daemonless, and rootless container management tool that provides an excellent alternative to Docker. Its Kubernetes integration, pod support, and OCI compatibility make it a powerful choice for containerized applications.