What AWS RDS Does

What AWS RDS Does

RDS handles:

• Database provisioning
• OS & database patching
• Automated backups
• Monitoring
• Scaling
• High availability & failover

You focus on data and applications, AWS manages the infrastructure.

🔹 Supported Database Engines

AWS RDS supports six relational database engines:

1. Amazon Aurora

• MySQL-compatible & PostgreSQL-compatible
• High performance, cloud-native
• Auto-scaling storage, fast failover

1. MySQL
2. PostgreSQL
3. MariaDB
4. Oracle
5. Microsoft SQL Server

🔹 Core RDS Components

1️⃣ DB Instance

• A virtual database server
• Defined by:
• Instance class (CPU/RAM)
• Storage type (GP2, GP3, IO1)

2️⃣ Storage

• General Purpose (SSD)
• Provisioned IOPS (SSD) – for high-performance workloads
• Magnetic (legacy)

🔹 High Availability (Multi-AZ)

• Automatically replicates data to a standby instance in another AZ
• Automatic failover during:
• Instance failure
• AZ outage
• Maintenance
• Improves availability, not read performance

🔹 Read Scaling (Read Replicas)

• Creates read-only copies of the database
• Used for:
• Read-heavy workloads
• Analytics
• Supported by MySQL, PostgreSQL, MariaDB, Aurora

🔹 Backups & Recovery

Automated Backups

• Enabled by default
• Retention: 1–35 days
• Point-in-time recovery

Manual Snapshots

• User-initiated
• Retained until deleted

🔹 Security Features

• VPC isolation
• Security Groups (firewall)
• IAM authentication (MySQL/PostgreSQL)
• Encryption at rest (KMS)
• Encryption in transit (SSL/TLS)

🔹 Monitoring & Performance

• Amazon CloudWatch metrics
• Enhanced Monitoring
• Performance Insights (query-level analysis)

🔹 RDS vs EC2 Database

FeatureRDSEC2OS Management❌ No✅ YesAutomated Backups✅❌ScalingEasyManualHigh AvailabilityBuilt-inManualCostMediumFlexible

🔹 Common Use Cases

• Web & mobile apps
• ERP / CRM systems
• E-commerce platforms
• SaaS applications
• Enterprise databases

🔹 Exam / Interview Tips

• Multi-AZ = High Availability
• Read Replicas = Read Scaling
• Aurora = Best performance
• Snapshots ≠ Automated backups
• RDS cannot SSH into DB host