Automatated DB Backup

Overview

Step

1. Dump database using mysqldump and compress the file at :00.
2. Upload the compressed file to S3 using aws s3 cp at :05.
3. Download the latest backup from S3 and restore it to an RDS database at :15.

• Keypoint: Ensure frequent backups for critical databases.
• Tools: AWS Lambda (for execution), EventBridge (for scheduling), S3 (for storage), and RDS (for restoration). A custom Lambda layer with mysqldump and mysql binaries handles database operations.

Implementation

1. Create a Lambda Function for Backup Tasks

• Create a Python-based Lambda function to handle the three steps. The function uses environment variables for sensitive information (e.g., database credentials, S3 bucket) and a custom layer for mysqldump and mysql binaries. The function is split into three tasks based on the time of execution (:00, :05, :15), determined by an EventBridge event.

2. Schedule with EventBridge

• EventBridge rules trigger the Lambda function at specific minutes (:00, :05, :15) each hour. Each rule passes a payload to indicate the task (dump, upload, or restore).

3. Lambda Function Code

• The Lambda function executes the appropriate task based on the event input. It:
  • Dumps the MySQL database to a file and compresses it using gzip.
  • Uploads the compressed file to S3.
  • Downloads the latest backup from S3 and restores it to RDS.

Monitoring and Alerts

1. Enable CloudWatch Logs for the Lambda function.
2. Set up CloudWatch Alarms for Lambda errors or duration to detect failures (e.g., database connection issues).