1. What is a Trusted Advisor?

AWS Trusted Advisor is an online tool that inspects your AWS environment and provides real-time recommendations to help you follow AWS best practices across five categories: cost optimization, performance, security, fault tolerance, and service limits.

Core Concept Trusted Advisor = automated best practice checker. It scans your account and recommends improvements across 5 pillars. Think of it as a consultant who continuously reviews your AWS setup and tells you what to fix. Some checks are free for all accounts; full checks require a Business/Enterprise Support plan.

2. Five Pillars

3. Free vs Full Checks

Important Warning Full Trusted Advisor checks require a Business or Enterprise Support plan. Basic and Developer support plans only get the 7 core security checks + service limits. This is a common exam question: "How to get all Trusted Advisor checks?" = upgrade to Business or Enterprise Support.

4. Trusted Advisor Automation

Trusted Advisor Automation (Business/Enterprise only):

Trusted Advisor Check: "Low Utilization EC2 Instances"
  → EventBridge Rule (match TA check result)
    → Lambda Function
      → Stop idle instances automatically
      → Send notification to the cost team via SNS

Trusted Advisor Check: "Security Groups - Unrestricted Access"
  → EventBridge Rule
    → Lambda
      → Automatically remove 0.0.0.0/0 from SG
      → Alert security team

5. Trusted Advisor vs Other Services

6. When to use

Use Trusted Advisor when you need automated best-practice recommendations across cost, performance, security, fault tolerance, and service limits.

Key exam triggers:

  1. "best practice checks"
  2. "reduce costs"
  3. "service limits"
  4. "security recommendations"
  5. "underutilized resources"
Exam Tip Trusted Advisor: "Best practice recommendations" = Trusted Advisor. 5 pillars: Cost, Performance, Security, Fault Tolerance, Service Limits. Free = 7 core checks only. Full = Business/Enterprise Support. "Detect idle EC2" = TA Cost Optimization. "Open SG warning" = TA Security. "Approaching service quota" = TA Service Limits. Automate with EventBridge (Business/Enterprise only).