Amazoan Relational Database Service (RDS) is a fully managed service provided by AWS (Amazon Web Services) that makes it easier to set up, operate, and scale relational databases in the cloud. It automates tasks such as hardware provisioning, database setup, patching, backups, and scaling. Here are some key features and components of AWS RDS:
Scalability: You can easily scale the compute and storage resources of your RDS instances based on your workload. This includes vertical scaling (increasing instance size) and horizontal scaling (using read replicas).
High Availability: You can deploy RDS instances with Multi-AZ (Availability Zone) configurations for high availability. This ensures automatic failover to a standby instance in case of hardware or software failures.
Automated Backups: RDS automatically takes daily backups of your database and retains transaction logs for point-in-time recovery. You can also manually trigger backups.
Security: RDS integrates with AWS Identity and Access Management (IAM) for controlling access. You can also encrypt data at rest and in transit using AWS Key Management Service (KMS).
Monitoring and Metrics: AWS provides monitoring through Amazon CloudWatch to keep track of database performance and resource utilization. You can set alarms and get notifications when certain thresholds are reached.
Managed Patching: AWS automatically applies patches to the RDS instances, ensuring they stay up-to-date with the latest security updates.
Cost Management: RDS offers different pricing models (on-demand and reserved instances) to optimize costs based on your usage patterns.
Database engines
- MySQL
- MariaDB
- Oracle (21c, 19c, 12c Release 1 and 2)
- PostgreSQL
- Amazon Aurora
- Microsoft SQL Server
Licenses
In RDS all versions of Microsoft SQL Server and Oracle (SE2) include a license.
Bring Your Own License is supported for Oracle EE and SE2.
Instance Classes:
| Class | Purpose | Use Case | Example Instances |
|---|---|---|---|
| General Purpose | Balanced CPU, memory, and network performance | Most workloads | db.t3, db.m5, db.m6g |
| Memory Optimized | High memory-to-CPU ratio | Memory-intensive applications | db.r5, db.r6g, db.x1e, db.u-6tb1.metal |
| Compute Optimized | High CPU performance | Compute-intensive workloads | db.c5, db.c6g |
| Storage Optimized | High storage throughput and low latency | High IOPS or large storage workloads | db.i3, db.d2 |
| Bursty/Low-Cost | Low-cost, burstable performance | Small apps or dev/test environments | db.t2 |
Comparison of RDS Storage Options:
| Storage Type | Use Case | Performance Characteristics | Max IOPS/Throughput | Max Storage Size |
|---|---|---|---|---|
| General Purpose (SSD) – gp3 | General-purpose workloads | Balanced price/performance with configurable IOPS and throughput | 16,000 IOPS and 1,000 MB/s throughput | 64 TB |
| Provisioned IOPS (SSD) – io1 | High-performance, I/O-intensive workloads | Low-latency, high throughput for transaction-heavy workloads | 64,000 IOPS (dependent on instance size) | 16 TB |
| Magnetic (Standard) | Low-budget, less demanding workloads | Lower performance and cost-effective but less predictable | 3,000 IOPS (typical) | 1 TB |
| Aurora Storage | High-availability, scalable workloads | Automatically scales, high availability and durability | Scales with workload automatically | 64 TB |
Amazon RDS Custom
Amazon RDS Custom is a managed database service designed for applications that require custom configurations and access to the underlying operating system (OS), which is not possible with standard RDS instances.
Full OS and DB Customization
Unlike standard RDS, RDS Custom allows you to access and modify the OS (e.g., installing third-party agents or making kernel changes).
You can also tweak database settings that are restricted in normal RDS.
Supports SQL Server & Oracle
As of now, RDS Custom is available for:
- Microsoft SQL Server
- Oracle
Automated Backups and Patching
Provides RDS-like automation, but you can choose when and how to apply patches.
Custom Monitoring and Control
You get full access to CloudWatch, CloudTrail, and AWS Systems Manager for deeper monitoring and automation.
Flexible Licensing
Supports Bring Your Own License (BYOL) for Oracle and SQL Server, allowing you to use existing database licenses.
SSH and RDP Access
You can SSH into the underlying EC2 instance (Linux) or use RDP for Windows-based instances, giving more control compared to standard RDS.