AWS Management & Governance

AWS provides services for managing multiple accounts, governing infrastructure as code, automating operations, and maintaining compliance across your organization.

Service Map

ServiceWhat It DoesWhen to Use
OrganizationsHierarchical account management, SCPs, consolidated billingMulti-account AWS environments
Control TowerPre-configured landing zone with guardrailsNew multi-account setup
CloudFormationYAML/JSON IaC for AWS resourcesInfrastructure provisioning
CDKProgrammatic IaC (TypeScript, Python, Java)Developers who prefer code over YAML
CLIUnified tool for AWS API accessAutomation, scripting, CI/CD
Systems ManagerPatch management, run commands, session manager, inventoryDay-2 operations, fleet management

Section Architecture

AWS Organizations (Root)
├── Security OU
│   ├── Security Account
│   └── Log Archive Account
├── Infrastructure OU
│   ├── Network Account
│   └── Shared Services Account
├── Production OU
│   ├── Prod Account
│   └── Staging Account
└── Development OU
    └── Dev Account

Control Tower → Enforces guardrails across OUs
CloudFormation → Provisions resources in each account
Systems Manager → Operates running fleets

How These Services Relate

Organizations is the foundation — it creates the account hierarchy and enables SCPs for access control. Control Tower sits on top of Organizations and sets up a pre-configured landing zone with preventive/detective guardrails. CloudFormation and CDK provision resources within accounts. CLI provides the command-line interface for all AWS APIs. Systems Manager manages the operational aspects of running EC2 instances and other resources.

References

Nuggets & Gotchas

  • Organizations SCPs don’t affect the management account itself: The management account (payer account) is not affected by Service Control Policies. You cannot restrict what the management account can do via SCPs.
  • CloudFormation stack sets require a trust relationship: To deploy across accounts via CloudFormation StackSets, the target accounts must first trust the administrative account. This is established via AWS RAM or within the StackSet itself.
  • Systems Manager requires SSM Agent on EC2 instances: If an EC2 instance doesn’t have SSM Agent installed and running, Systems Manager cannot manage it. For Amazon Linux 2 and recent AMIs, SSM Agent is pre-installed.
  • AWS CLI credentials take precedence over instance profile: If you configure AWS CLI credentials (via aws configure) on an EC2 instance that also has an instance profile, the CLI credentials take precedence. This can cause unexpected behavior in automation scripts.
  • Control Tower creates its own CloudTrail and Config rules: When you set up Control Tower, it enables CloudTrail in all accounts and creates AWS Config rules. This has cost implications — monitor CloudTrail log volume across all accounts.