AWS Relational Database Service (RDS) Overview

AWS RDS is a managed database service that supports SQL query language. It simplifies database management in the cloud by offering automated provisioning, patching, backups, and more.

Supported Database Engines

• Amazon RDS supports several database engines, including:
  • PostgreSQL
  • MySQL
  • MariaDB
  • Oracle
  • Microsoft SQL Server
  • IBM DB2
  • Aurora (AWS's proprietary database)

Advantages of Using RDS Over EC2-Hosted Databases

• Managed Service: AWS handles database provisioning, OS patching, and backups.
• Automatic Backups: Enables point-in-time recovery.
• Monitoring Dashboards: Offers insights into database performance.
• Read Replicas: Improves read performance through duplication.
• Multi AZ Deployments: Enhances availability and disaster recovery.
• Maintenance Windows: For seamless upgrades.
• Scaling: Supports both vertical (instance size) and horizontal (read replicas) scaling.
• Storage: Utilizes EBS (gp2 or io1 volumes), ensuring durability and performance.

Limitations

• No SSH Access: Users cannot access the underlying EC2 instance of the RDS database.

RDS Storage Auto Scaling

• Automatic Storage Scaling: Detects and scales database storage as needed to prevent running out of space.
• Configuration: Users set a maximum storage threshold to control scaling limits.
• Criteria for Scaling: Storage scales up if free space drops below 10% of the allocated space, the low storage state persists for more than five minutes, and at least six hours have passed since the last modification.
• Supported Engines: All RDS database engines support auto-scaling, facilitating management for applications with unpredictable workloads.