Pgpool-II Multi-Architecture Docker Image

Optimized Dockerfile for building lightweight, multi-architecture (AMD64 and ARM64) Docker images of Pgpool-II. The image is built using a multi-stage approach, ensuring that the runtime includes only the essential libraries, and is based on a distroless image for enhanced security and minimal size.

Features

• Multi-Architecture Support: Build for both AMD64 and ARM64 using Docker Buildx.
• Lightweight Runtime: Based on distroless for a minimal attack surface.
• Optimized Build Process: Includes only the required libraries for Pgpool-II to function.
• Production-Ready: Designed for secure, high-performance production environments.

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How It Works

This Dockerfile uses a multi-stage build process:

1. Build Stage:
   • Installs Pgpool-II and all necessary libraries using apt.
   • The installation is isolated to keep the runtime clean.
2. Runtime Stage:
   • Copies only the required binaries and libraries from the build stage.
   • Uses a distroless image to minimize the runtime footprint.

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Usage

Build the Image

Use Docker Buildx to build the image for multiple architectures:

docker buildx build --platform linux/amd64,linux/arm64 -t your-repo/pgpool:latest --push .

Run the Container

Start the container using the built image:

docker run -d \
  --name pgpool \
  -v $(pwd)/configs/pgpool.conf:/etc/pgpool/pgpool.conf \
  -p 9999:9999 \
  your-repo/pgpool:latest

Verify the Running Container

Check the status of the container:

docker ps

Inspect the logs:

docker logs pgpool

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Configuration

Custom Configuration File

You can provide your own pgpool.conf by mounting it into the container:

docker run -d \
  -v /path/to/your/pgpool.conf:/etc/pgpool/pgpool.conf \
  your-repo/pgpool:latest

Environment Variables

If needed, set environment variables for additional customization:

docker run -d \
  -e PGPOOL_USER=your_user \
  -e PGPOOL_PASSWORD=your_password \
  your-repo/pgpool:latest

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Example Commands

Enter the Container

For debugging or manual interaction:

docker exec -it pgpool /bin/sh

Stop the Container

docker stop pgpool

Remove the Container

docker rm pgpool

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Development Notes

Adding Missing Libraries

If the runtime reports missing libraries, add them in the build stage and copy them to the runtime stage. Use ldd to check dependencies:

ldd /path/to/pgpool

Add the necessary libraries to the Dockerfile using:

RUN apt-get install -y <library_name>
COPY --from=builder /usr/lib/*-linux-gnu/<library_name> /usr/lib/

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Contributing

Contributions are welcome! Feel free to open issues or submit pull requests for improvements or bug fixes.

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License

This project is licensed under the MIT License.