peterweissdk/keepalived-db-cluster repository overview

⁠💾 Keepalived container with Galera check-script

A lightweight, Alpine-based Docker container for running Keepalived with VRRP (Virtual Router Redundancy Protocol) support and MariaDB Galera cluster state monitoring.

💡 This container is a slightly modified version of peterweissdk/keepalived⁠, with an added check script for monitoring the state of a MariaDB Galera cluster. It is designed to be used in conjunction with peterweissdk/galera-compose⁠, which sets up and runs a MariaDB Galera cluster.

⁠✨ Features

• Alpine-based: Lightweight and secure base image
• VRRP support: High availability with Virtual Router Redundancy Protocol (VRRP)
• Easy Configuration: Configure Keepalived using environment variables, and service check-scripts
• Health Checks: Monitor service health with built-in Docker health checks

⁠🚀 Quick Start

Run the container:

# Pull the image
docker pull ghcr.io/peterweissdk/keepalived-db-cluster:latest

# Run with custom configuration
docker run -d \
  --name keepalived \
  --restart=unless-stopped \
  --cap-add=NET_ADMIN \
  --cap-add=NET_BROADCAST \
  --cap-add=NET_RAW \
  --net=host \
  --env-file .env \
  keepalived-db-cluster:latest

# Run the container using the provided Docker Compose and .env file
docker compose up -d

⁠🔧 Configuration

⁠Environment Variables

⁠Required Capabilities

• NET_ADMIN: For network interface configuration
• NET_BROADCAST: For VRRP advertisements
• NET_RAW: For raw socket access

⁠Service Check-Script

Create a script to run at regular intervals to check the state of your service. Create a bind mount and copy the script into it

• Name of script: check-script.sh
• Bind mount point: /usr/local/scripts/
• Runs at regular intervals: 2 seconds

⁠🏗️ Building from Source

# Clone the repository
git clone https://github.com/peterweissdk/keepalived-db-cluster.git
cd keepalived-db-cluster

# Build the image
docker build -t keepalived-db-cluster:latest .

⁠📝 Directory Structure

keepalived-db-cluster/
├── check-script
│   └── check-script.sh
├── conf/
│   └── keepalived.conf_tpl
├── scripts/
│   └── check_and_run.sh
├── .env
├── Dockerfile
├── docker-entrypoint.sh
├── healthcheck.sh
├── docker-compose.yml
├── LICENSE
└── README.md

⁠🔍 Health Check

The container includes a comprehensive health check system that monitors:

1. Keepalived Process Status

   • Verifies the keepalived daemon is running

2. Virtual IP environment variable

   • Verifies the VIRTUAL_IPS environment variable is set

View health status:

docker inspect --format='{{.State.Health.Status}}' keepalived-db-cluster

View detailed health check history:

docker inspect --format='{{json .State.Health}}' keepalived-db-cluster | jq

Watch health status in real-time:

watch -n 5 'docker inspect --format="{{.State.Health.Status}}" keepalived-db-cluster'

⁠🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

⁠🆘 Support

If you encounter any issues or need support, please file an issue on the GitHub repository.

⁠📄 License

This project is licensed under the GNU GENERAL PUBLIC LICENSE v3.0 - see the LICENSE⁠ file for details.