AWS has tools that monitor cloud infrastructure for cost, compliance, and security. Ones related directly to monitoring, managing RDS include AWS Config, AWS CloudTrail and AWS Trusted Advisor.

AWS Config is a service that can assess, audit, and evaluate configurations of AWS resources, such as RDS to ensure compliance. Config continuously monitors and records RDS configuration changes and can send an alert using the Amazon Simple Notification Service, SNS, when a change violates a rule. For a deeper understanding of AWS Config, Cloud Academy has courseware available:

AWS Config: An Introduction

How to Implement & Enable Logging Across AWS Services (Part 1 of 2)

AWS CloudTrail is an auditing service that records programmatic access to AWS services. This enables governance, compliance, operational auditing, and risk auditing of an AWS account. CloudTrail captures all of the API calls made to RDS, including calls from the RDS Console for monitoring and analysis. CloudTrail provides an event history of AWS account activity and includes actions taken through the Management Console, AWS SDKs, Command-line tools, and other AWS services. It simplifies security analysis, resource change tracking and troubleshooting. Information collected from CloudTrail can provide information such as requests made to RDS, the IP address that made the request, who made it, and when it was made. By default, AWS CloudTrail provides access to the most recent programmatic events made to RDS, but it is possible to create a trail that collects information for longterm storage and analysis. To learn more about AWS CloudTrail, Cloud Academy has courseware available:

AWS CloudTrail: An Introduction

AWS Trusted Advisor is a service that analyzes AWS Cloud resources and compares them to best practices. It automatically looks at service usage inside an account and reports on common cost, performance, security, and fault tolerance optimizations. It then provides suggested actions for remediation.

Trusted Advisor checks for RDS include ones for Idle Database instances, risks with RDS Security Group access, issues with RDS backups, and RDS Multi-AZ configurations. For example, one of the Trusted Advisor checks for RDS is permission settings on database snapshots. It alerts when a snapshot is marked as public as this means it can be seen by every AWS account. To learn more about AWS Trusted Advisor, Cloud Academy has some courseware available:

Using AWS Trusted Advisor to Follow and Implement Best Practices