Debian Base Container

A minimal Debian container with customizable version support. This container provides a clean Debian base image with version flexibility for various use cases.

Features

• Multi-Architecture Support: Available for amd64 and arm64 architectures
• Version Flexibility: Supports multiple Debian versions via build args
• Minimal Footprint: Uses Debian’s slim variants for reduced image size
• Automated Builds: Integrated with upstream monitoring for version updates
• Clean Base: Perfect starting point for custom applications

Usage

With Docker Compose

version: '3.8'
services:
  debian-app:
    build:
      context: .
      args:
        VERSION: bookworm-slim
    volumes:
      - ./app:/app
    working_dir: /app
    command: bash

Direct Docker Run

# Use default version
docker run -it --rm debian-base bash

# Specify version
docker build --build-arg VERSION=bullseye-slim -t debian-base .
docker run -it --rm debian-base bash

Build Arguments

• VERSION - Debian version tag (default: defined in version.sh)
  • bookworm-slim - Debian 12 (current stable)
  • bullseye-slim - Debian 11 (oldstable)
  • bookworm - Full Debian 12 image
  • bullseye - Full Debian 11 image

Common Use Cases

1. Application Base: Starting point for custom applications
2. Development Environment: Clean environment for testing
3. CI/CD Base: Consistent build environment
4. Package Testing: Testing packages across Debian versions

Building

cd debian
docker-compose build

# Or with specific version
docker build --build-arg VERSION=bookworm-slim -t debian-base .

Version Management

This container uses automated version detection for the latest Debian releases:

./version.sh          # Current version
./version.sh latest    # Latest available version

The version script automatically detects the latest stable Debian release and updates accordingly.

Security

Base Security

• Uses official Debian base images
• Minimal attack surface with slim variants
• Regular security updates through automated rebuilds
• No additional packages installed by default

User Security

• No hardcoded passwords: User created without password (login via docker exec or SSH keys)
• Non-root by default: Container runs as debian user
• Sudo access: Passwordless sudo for container operations

Runtime Hardening (Recommended)

# Secure runtime configuration
docker run -it --rm \
  --read-only \
  --tmpfs /tmp \
  --tmpfs /run \
  --cap-drop ALL \
  --security-opt no-new-privileges:true \
  debian-base bash

Docker Compose Security Template

services:
  debian:
    image: ghcr.io/oorabona/debian:latest
    read_only: true
    tmpfs:
      - /tmp
      - /run
    cap_drop:
      - ALL
    security_opt:
      - no-new-privileges:true

Advanced Migration Tool - export.sh

The export.sh script is a powerful migration utility for creating custom Debian containers that replicate your host system’s configuration. This is particularly useful for:

Use Cases

1. System Migration: Create a containerized version of your current Debian/Ubuntu system
2. Development Environment Replication: Share exact development environments with team members
3. Legacy System Containerization: Convert bare-metal installations to containers
4. Custom Base Images: Create specialized base images with your exact package set

Features

• Package Migration: Copy installed packages from host to container
• Configuration Migration: Transfer /etc and /home directories
• Flexible Options: Granular control over what gets migrated
• Multiple Package Managers: Support for apt, apt-get, and aptitude
• Selective Exclusions: Exclude specific directories or packages

Usage

# Basic usage - create container with same packages
./export.sh --packages=install --version=bookworm

# Advanced usage - full system migration
./export.sh \
  --version=bookworm-slim \
  --locales="en_US fr_FR" \
  --packages=install \
  --package-manager=apt \
  --copy-etc \
  --copy-etc-exclude="secrets,private" \
  --copy-home \
  --copy-home-exclude=".cache,.tmp" \
  --omit-linux-kernel

# Help and options
./export.sh --help

Options

• --version=<version> - Target Debian version (e.g., bookworm, bullseye)
• --locales=<locales> - Locales to install (e.g., “en_US fr_FR”)
• --packages=[none|copy|install] - Package management strategy
  • none - Don’t manage packages
  • copy - Copy package list only
  • install - Copy and install packages
• --package-manager=[apt|apt-get|aptitude] - Choose package manager
• --copy-etc - Copy /etc directory configuration
• --copy-etc-exclude=<dirs> - Exclude directories from /etc (comma-separated)
• --copy-home - Copy /home directory
• --copy-home-exclude=<dirs> - Exclude directories from /home
• --omit-linux-kernel - Skip Linux kernel packages

Output

The script creates a debian-<version>.tar file containing your migrated system that can be imported as a Docker image:

# Import the exported container
docker import debian-bookworm.tar my-custom-debian:latest

# Run your migrated system
docker run -it my-custom-debian:latest bash

Security Considerations

• Review what gets copied before running
• Exclude sensitive directories with --copy-etc-exclude and --copy-home-exclude
• Consider using package-only migration for production environments
• Test exported containers in isolated environments first