ECS Instance Balancer

This project provides an automated solution for balancing ECS (Elastic Container Service) instances in AWS. It helps optimize resource utilization by monitoring and rebalancing instances when necessary.

Configuration

The application uses a config.json file with the following structure:

{
  "region": "<region>",
  "targetClusterArn": "arn:aws:ecs:<region>:<user-id>:cluster/<cluster-name>",
  "capacityProvider": "EC2",
  "autoScalingGroupName": "<asg-name>"
}

Configuration Parameters

• region: AWS region where your ECS cluster is located
• targetClusterArn: ARN of the ECS cluster to monitor
• capacityProvider: Type of capacity provider (EC2 or FARGATE)
• autoScalingGroupName: Name of the Auto Scaling Group associated with the cluster

Balancing Process

The balancer follows these steps to optimize instance distribution:

1. Instance Discovery: Retrieves all ECS instances in the target cluster
2. Task Analysis: Gathers information about all running tasks
3. Resource Calculation:
   • Calculates resource usage for each instance
   • Determines if rebalancing is needed based on resource utilization
4. Instance Termination: If rebalancing is required, terminates the target instance
   • The Auto Scaling Group will automatically launch a new instance
   • ECS will redistribute tasks to the new instance

Installation

pnpm install

Usage

1. Copy config.json.example to config.json:

cp config.json.example config.json

2. Edit config.json with your AWS ECS cluster details:

{
  "region": "your-aws-region",
  "targetClusterArn": "your-ecs-cluster-arn",
  "capacityProvider": "EC2",
  "autoScalingGroupName": "your-asg-name"
}

3. Start the balancer:

pnpm start

Development

This project is written in TypeScript and uses:

• AWS SDK for interacting with ECS
• Node.js runtime environment
• pnpm as the package manager

License

MIT