How To Install Podman on AlmaLinux 10

Container technology has revolutionized how we deploy and manage applications in modern computing environments. Podman, short for Pod Manager, stands as one of the most compelling alternatives to Docker, offering a daemon-less architecture that prioritizes security and efficiency. This comprehensive guide will walk you through the complete process of installing and configuring Podman on AlmaLinux 10, ensuring you have all the tools necessary for effective container management.

What is Podman and Why Choose It Over Docker?

Podman is a daemon-less container engine designed to develop, manage, and run OCI (Open Container Initiative) containers on Linux systems. Unlike Docker, which requires a central daemon running with root privileges, Podman operates without any background service, making it inherently more secure and resource-efficient.

The key advantages of Podman include its rootless operation capability, which allows users to run containers without requiring root privileges. This architectural difference eliminates many security vulnerabilities associated with daemon-based container engines. Additionally, Podman provides Docker-compatible command-line interface, making the transition from Docker seamless for most users.

AlmaLinux 10 serves as an excellent foundation for containerized workloads due to its enterprise-grade stability and security features. The distribution’s commitment to long-term support and compatibility with Red Hat Enterprise Linux makes it an ideal choice for production container deployments. When combined with Podman’s security-first approach, AlmaLinux 10 creates a robust platform for modern container orchestration.

Prerequisites and System Requirements

Before beginning the installation process, ensure your AlmaLinux 10 system meets the minimum requirements. You’ll need a fresh AlmaLinux 10 installation with at least 2GB of RAM and 10GB of available disk space. A stable internet connection is essential for downloading container images and updates.

Administrative privileges are mandatory for the installation process. Ensure you have access to a user account with sudo privileges or direct root access. The installation process will require downloading packages from official repositories, so verify your network connectivity before proceeding.

Storage considerations are crucial for container operations. Podman stores container images and data in the user’s home directory by default when running in rootless mode. Plan for adequate storage space, especially if you intend to work with large container images or multiple containers simultaneously.

Understanding Podman’s Daemon-less Architecture

Podman’s daemon-less design represents a fundamental shift from traditional container engines. Unlike Docker, which relies on a central daemon process running with root privileges, Podman spawns containers directly as child processes. This approach eliminates the single point of failure that daemon-based systems present.

The security implications of this architecture are significant. Each container runs as a separate process under the user’s privileges, preventing privilege escalation attacks that could compromise the entire system. User namespaces provide additional isolation, ensuring that containers cannot access resources outside their designated scope.

OCI standards compliance ensures compatibility with existing container ecosystems. Podman can run Docker images without modification and supports the same registry protocols. This compatibility means you can leverage existing Docker Hub images and private registries without any additional configuration.

Step-by-Step Installation Guide

System Preparation

Begin by updating your AlmaLinux 10 system to ensure you have the latest packages and security updates. Open a terminal and execute the following commands:

sudo dnf update -y
sudo dnf upgrade -y

This process may take several minutes depending on your system’s current state and available updates. After the update completes, it’s recommended to reboot your system to ensure all kernel updates are properly applied:

sudo reboot

Installing Podman via DNF

Podman is available directly from AlmaLinux repositories, eliminating the need for third-party package sources. The installation process is straightforward using the DNF package manager:

sudo dnf install podman -y

The DNF package manager will automatically resolve dependencies and install all required components. This typically includes container runtime dependencies and supporting libraries necessary for Podman’s operation.

Verify the installation by checking the installed version:

podman --version

You should see output similar to podman version 5.2.2 or a newer version, confirming successful installation.

Post-Installation Configuration

Configure Podman for optimal performance by setting up the necessary runtime environment. Check the installation details and system configuration:

podman info

This command displays comprehensive information about your Podman installation, including storage drivers, registry configuration, and system capabilities.

Enable lingering for your user account to ensure containers can persist across login sessions:

sudo loginctl enable-linger $(whoami)

This configuration is particularly important for rootless container operations and long-running services.

Verification and Testing

Basic Functionality Tests

Test your Podman installation with a simple container run. Pull and run the hello-world container to verify basic functionality:

podman pull hello-world:latest
podman run hello-world:latest

This test confirms that Podman can successfully pull images from container registries and execute containers. The hello-world container provides a simple verification that your installation is working correctly.

Advanced Testing Scenarios

Run a more complex container to test networking and persistence capabilities:

podman run -d --name test-web -p 8080:80 nginx:latest

This command creates a detached NGINX container with port mapping, testing both container lifecycle management and network configuration. Access the web server by navigating to http://localhost:8080 in your browser.

Test container persistence by stopping and starting the container:

podman stop test-web
podman start test-web

Clean up the test container when finished:

podman stop test-web
podman rm test-web

Essential Podman Commands and Usage

Basic Container Operations

Master the fundamental Podman commands for effective container management. The most commonly used commands include:

# List running containers
podman ps

# List all containers (including stopped)
podman ps -a

# List downloaded images
podman images

# Remove a container
podman rm container-name

# Remove an image
podman rmi image-name

Container lifecycle management follows intuitive patterns similar to Docker. Create, start, stop, and remove containers using straightforward commands that mirror Docker’s interface.

Docker Compatibility Layer

Set up Docker command aliases for seamless transition from Docker workflows. Add the following alias to your shell configuration:

echo 'alias docker=podman' >> ~/.bashrc
source ~/.bashrc

This alias allows you to use familiar Docker commands while leveraging Podman’s improved architecture. Most Docker commands work identically with Podman, making the transition virtually transparent.

Advanced Pod Management

Podman’s pod functionality extends beyond simple container management. Create multi-container pods that share network and storage resources:

podman pod create --name my-pod
podman run -d --pod my-pod nginx:latest
podman run -d --pod my-pod redis:latest

This capability enables complex application deployments with shared resources and simplified networking.

Installing Additional Tools

Podman Compose Installation

Podman Compose enables multi-container applications using familiar Docker Compose syntax. For AlmaLinux 10, install Podman Compose using Python pip:

sudo dnf install python3 python3-pip python3-devel -y
sudo pip3 install podman-compose

Verify the installation by checking the version:

podman-compose --version

This tool allows you to use existing Docker Compose files with Podman, facilitating easy migration of complex applications.

Cockpit Integration for Web Management

Install Cockpit-Podman for web-based container management:

sudo dnf install cockpit-podman -y

Enable and start the Cockpit service:

sudo systemctl enable --now cockpit.socket

Access the web interface by navigating to https://your-server-ip:9090 in your browser. This provides a graphical interface for container management, making it easier to monitor and control containers visually.

Configuration and Optimization

Storage Configuration

Configure storage drivers for optimal performance based on your system’s requirements. Podman supports multiple storage backends, with overlay being the default for most systems.

Check your current storage configuration:

podman info | grep -A 10 "Storage Driver"

Optimize storage performance by configuring appropriate storage options in /etc/containers/storage.conf for system-wide settings or ~/.config/containers/storage.conf for user-specific configuration.

Security Configuration

Configure SELinux integration for enhanced security. AlmaLinux 10 includes SELinux by default, and Podman integrates seamlessly with SELinux policies.

Verify SELinux status:

getenforce

Enable additional security features by configuring user namespaces and security policies according to your organization’s requirements.

Troubleshooting Common Issues

Installation Problems

Repository access issues can occur during installation. If you encounter package not found errors, verify your repository configuration:

sudo dnf repolist

Dependency conflicts may arise with existing packages. Use the --allowerasing flag to resolve conflicts:

sudo dnf install podman --allowerasing

Runtime Issues

Container startup failures often relate to permission or resource issues. Check container logs for detailed error information:

podman logs container-name

Storage space problems can prevent container operations. Monitor disk usage and clean up unused images:

podman system df
podman image prune

Performance Optimization

Network performance issues may require adjusting network settings. Configure custom networks for better performance:

podman network create custom-network

Resource allocation problems can be addressed by setting appropriate limits during container creation:

podman run --memory=1g --cpus=1 container-name

Best Practices and Security

Security Best Practices

Implement rootless container execution as the primary security measure. Run containers as non-root users whenever possible to minimize security risks. Configure user namespaces properly to ensure proper isolation between containers and the host system.

Regular image updates are crucial for maintaining security. Implement automated processes to scan and update container images regularly:

podman images --format "table {{.Repository}}:{{.Tag}}"

Network security configuration should restrict container access to necessary ports and services only. Use custom networks to isolate container communication from the host network.

Performance Optimization

Resource management requires careful consideration of CPU and memory allocation. Monitor container resource usage and adjust limits accordingly:

podman stats

Storage optimization involves regular cleanup of unused images and containers. Implement automated cleanup processes to maintain system performance:

podman system prune -a

Comparison: Podman vs Docker

Key Architectural Differences

Podman’s daemon-less architecture eliminates the single point of failure present in Docker’s daemon-based system. This design choice significantly improves system stability and security by reducing the attack surface.

Security model differences are substantial. Docker’s daemon runs with root privileges, while Podman can operate entirely in user space. This fundamental difference makes Podman inherently more secure for multi-user environments.

Migration Considerations

Command compatibility between Docker and Podman is nearly complete. Most Docker commands work identically with Podman, simplifying the migration process. However, some Docker-specific features may require alternative approaches in Podman.

Tool integration may require updates to CI/CD pipelines and development workflows. Plan for testing and validation phases when migrating from Docker to Podman in production environments.

Advanced Usage and Integration

Systemd Integration

Podman integrates seamlessly with systemd, enabling containers to run as system services. Generate systemd service files for containers:

podman generate systemd --name container-name --files

This integration allows containers to start automatically at boot and restart on failure, providing production-ready container management.

Kubernetes Integration

Podman supports Kubernetes YAML files directly, enabling local testing of Kubernetes deployments:

podman play kube deployment.yaml

This capability bridges the gap between local development and production Kubernetes environments.

Congratulations! You have successfully installed Podman. Thanks for using this tutorial for installing Podman containers on your AlmaLinux OS 10 system. For additional help or useful information, we recommend you check the official Podman website.