RDS is a managed relational database. You bring the data; AWS handles patching, backups, and failover. It runs MySQL, PostgreSQL, MariaDB, Oracle, SQL Server, and Amazon’s own Aurora.
Remember this one distinction
The test asks it constantly and the two sound alike: Multi-AZ is about staying up; Read Replicas are about handling more reads. Multi-AZ keeps a standby in another AZ and fails over automatically — it’s insurance, not performance. Read Replicas are copies you send read traffic to when reports are drowning the database.
Test yourself
A reporting workload is overwhelming the primary database with read queries. Writes are unaffected. What is the best solution?
- Enable Multi-AZ
- Add Read Replicas
- Increase the backup retention period
- Move to a larger EBS volume
👉 Click to reveal the answer & explanation
Correct answer: B. Read Replicas offload and scale read traffic. Multi-AZ (A) is for failover/HA and wouldn’t take a single query off the primary; backup retention (C) and disk size (D) don’t address read load.
Related topics
Amazon DynamoDB · Amazon VPC · Amazon EC2
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