Introduction
ElasticRelay is a high-performance, production-ready Change Data Capture (CDC) gateway that enables real-time data synchronization from multiple database sources to Elasticsearch.
What is ElasticRelay?
ElasticRelay captures database changes in real-time and synchronizes them to Elasticsearch, making your data instantly searchable. It supports:
- MySQL 5.7+ - Using binlog-based CDC
- PostgreSQL 10+ - Using logical replication
- MongoDB 4.0+ - Using change streams
Key Features
Zero-Code Configuration
Get started with simple JSON configuration files. No programming required.
Multi-Database Support
Connect to multiple databases simultaneously and sync them to Elasticsearch with a single ElasticRelay instance.
Built-in Reliability
- Automatic Checkpointing: Never lose data with automatic progress tracking
- Dead Letter Queue (DLQ): Failed events are safely stored for retry
- Automatic Recovery: Seamlessly resume from where you left off after restarts
High Performance
- Parallel Processing: Multi-threaded snapshot synchronization for large tables
- Optimized Throughput: Efficient batching and bulk operations
- Memory Efficient: Smart memory management for handling large datasets
Production-Ready
- Battle-Tested: Used in production environments processing millions of events
- Monitoring: Built-in metrics and health checks
- Flexible Deployment: Run as a standalone binary, Docker container, or Kubernetes pod
Use Cases
Real-Time Search
Make your database data instantly searchable by syncing to Elasticsearch in real-time.
Analytics & Reporting
Build real-time dashboards and analytics on top of your operational data.
Data Lake Integration
Stream database changes to Elasticsearch as part of your data lake architecture.
Microservices Data Sync
Keep search indexes in sync with your microservices databases.
How It Works
- Connect: ElasticRelay connects to your database and starts listening for changes
- Capture: Database changes (INSERT, UPDATE, DELETE) are captured in real-time
- Transform: Data is transformed to match Elasticsearch document format
- Sync: Changes are efficiently synced to Elasticsearch with automatic retry
- Monitor: Track progress with built-in checkpointing and metrics
Architecture Overview
┌─────────────┐
│ MySQL │───┐
└─────────────┘ │
│
┌─────────────┐ │ ┌──────────────┐ ┌──────────────┐
│ PostgreSQL │───┼───▶│ ElasticRelay │───▶│Elasticsearch │
└─────────────┘ │ └──────────────┘ └──────────────┘
│
┌─────────────┐ │
│ MongoDB │───┘
└─────────────┘
What’s Next?
- Installation - Install ElasticRelay
- Quick Start - Get up and running in 5 minutes
- Configuration - Configure your first CDC pipeline