2.2.2.3. Centralized Account Management (Organizations, Control Tower)
2.2.2.3. Centralized Account Management (Organizations, Control Tower, Trusted Advisor)
Centralized management means governing 100+ accounts without logging into each one.
AWS Organizations features for the exam:
- Consolidated billing: Single payment, volume discounts, Reserved Instance sharing
- SCPs: Organizational-level permission boundaries
- Tag policies: Enforce consistent tagging (e.g.,
Environmentmust bedev|staging|prod) - Backup policies: Enforce AWS Backup plans across accounts
- AI services opt-out policies: Control data use for AI improvement
Control Tower guardrails:
| Type | Mechanism | Example |
|---|---|---|
| Preventive (mandatory) | SCP | Disallow Configuration Changes to CloudTrail (denies StopLogging, DeleteTrail, UpdateTrail, PutEventSelectors on the aws-controltower-* trails) |
| Preventive (strongly recommended) | SCP | Disallow public S3 buckets |
| Detective (mandatory) | Config rule | Detect CloudTrail disabled |
| Detective (elective) | Config rule | Detect unencrypted EBS volumes |
AWS Trusted Advisor provides account-level recommendations: cost optimization, performance, security, fault tolerance, and service limits. Full features require Business or Enterprise Support.
Exam Trap: By default, Organizations tag policies only report non-compliant tag values — the resource is still created. Enforcement (enforced_for) blocks non-compliant tagging operations only on the resource types you list, and it checks tag values, not presence: untagged resources aren't evaluated. Required tag keys (report_required_tag_for) are checked only in IaC deployments, e.g. by the AWS::TagPolicies::TaggingComplianceValidator CloudFormation hook. To prevent resource creation without required tags, use an SCP:
{
"Effect": "Deny",
"Action": "ec2:RunInstances",
"Resource": "*",
"Condition": {
"Null": {"aws:RequestTag/Environment": "true"}
}
}