How to Set Up Podman as a Docker Alternative

How to Set Up Podman as a Docker Alternative

Podman is a daemonless container engine that runs containers without requiring a root-level daemon process. It provides a Docker-compatible CLI, making it a drop-in replacement for most Docker workflows on your Breeze server.

Why Choose Podman

• Daemonless — no background daemon means fewer security risks and simpler management
• Rootless containers — run containers as a non-root user for better security
• Docker-compatible — same CLI commands and Dockerfile support
• Pod support — group related containers into pods, similar to Kubernetes pods
• Systemd integration — generate systemd service files directly from containers

Installing Podman

# Ubuntu 22.04+
sudo apt update && sudo apt install -y podman

# RHEL/AlmaLinux/Rocky 9
sudo dnf install -y podman

# Verify installation
podman --version
podman info

Running Containers with Podman

Podman uses the same syntax as Docker:

# Run an Nginx container
podman run -d --name web -p 8080:80 nginx:latest

# List running containers
podman ps

# View logs
podman logs web

# Execute a command inside the container
podman exec -it web bash

# Stop and remove
podman stop web && podman rm web

Rootless Containers

Run containers as a non-root user for enhanced security:

# Ensure user namespaces are configured
grep $(whoami) /etc/subuid
grep $(whoami) /etc/subgid

# If not present, add them
sudo usermod --add-subuids 100000-165535 --add-subgids 100000-165535 $(whoami)
podman system migrate

# Run rootless container
podman run -d --name myapp -p 8080:80 myapp:latest

Working with Pods

Pods group containers that share network and IPC namespaces:

# Create a pod
podman pod create --name webapp -p 8080:80 -p 5432:5432

# Add containers to the pod
podman run -d --pod webapp --name app nginx:latest
podman run -d --pod webapp --name db \
  -e POSTGRES_PASSWORD=secret postgres:16

# List pods
podman pod ps

# Stop entire pod
podman pod stop webapp

Generating Systemd Services

Let Podman create systemd unit files for automatic container management:

# Generate a systemd service for a container
podman generate systemd --new --name myapp > ~/.config/systemd/user/myapp.service

# Enable and start
systemctl --user daemon-reload
systemctl --user enable --now myapp.service

# Check status
systemctl --user status myapp.service

Docker Compose Compatibility

Use podman-compose or Docker Compose with the Podman socket:

# Install podman-compose
pip install podman-compose

# Use existing docker-compose.yml files
podman-compose up -d
podman-compose ps
podman-compose down

# Or enable the Podman socket for Docker Compose
systemctl --user enable --now podman.socket
export DOCKER_HOST=unix://$XDG_RUNTIME_DIR/podman/podman.sock
docker compose up -d

Docker Alias for Seamless Migration

# Add to ~/.bashrc for Docker-like experience
alias docker=podman

Best Practices

• Use rootless mode for all application containers on your Breeze server
• Generate systemd services for containers that should start at boot
• Use pods when containers need to communicate over localhost
• Configure container registries in /etc/containers/registries.conf
• Regularly run podman system prune to clean up unused images and containers