AWS Organizations is a powerful account management service that enables you to consolidate multiple AWS accounts into an organization that you create and centrally manage. This service is essential for enterprises dealing with organizational complexity at scale.
Key components include:
**Organiza…AWS Organizations is a powerful account management service that enables you to consolidate multiple AWS accounts into an organization that you create and centrally manage. This service is essential for enterprises dealing with organizational complexity at scale.
Key components include:
**Organizational Units (OUs):** Hierarchical groupings of accounts that allow you to apply policies based on business functions, environments (dev/test/prod), or regulatory requirements. OUs can be nested up to five levels deep.
**Service Control Policies (SCPs):** JSON-based policies that define the maximum available permissions for member accounts. SCPs act as guardrails, restricting what actions accounts can perform even if IAM policies allow them. They follow an inheritance model through the OU hierarchy.
**Consolidated Billing:** All member accounts roll up to a single payer account, enabling volume discounts, Reserved Instance sharing, and Savings Plans benefits across the organization.
**AWS Resource Access Manager (RAM):** Works alongside Organizations to share resources like VPC subnets, Transit Gateways, and License Manager configurations across accounts.
**Integration Benefits:** Organizations integrates with numerous AWS services including CloudTrail for centralized logging, Config for compliance monitoring, Security Hub for security posture management, and Control Tower for automated landing zone setup.
**Best Practices:**
- Use a dedicated management account with minimal workloads
- Implement a multi-account strategy separating workloads by function
- Apply least-privilege SCPs at appropriate OU levels
- Enable AWS CloudTrail organization trails for comprehensive auditing
- Leverage delegated administrator capabilities for security services
**Common Architectures:** Solutions architects typically design landing zones with separate OUs for security, infrastructure, sandbox, and workload accounts. This separation provides blast radius reduction, simplified compliance boundaries, and cleaner cost allocation.
Understanding Organizations is fundamental for designing enterprise-scale AWS architectures that balance governance, security, and operational efficiency.
AWS Organizations - Complete Guide for Solutions Architect Professional
Why AWS Organizations is Important
AWS Organizations is a foundational service for managing multi-account AWS environments at enterprise scale. As organizations grow, they require robust governance, consolidated billing, and centralized policy management across hundreds or even thousands of AWS accounts. Understanding AWS Organizations is critical for the Solutions Architect Professional exam because it underpins nearly every architectural decision involving organizational complexity, security boundaries, and cost management.
What is AWS Organizations?
AWS Organizations is an account management service that enables you to consolidate multiple AWS accounts into an organization that you create and centrally manage. It provides:
• Consolidated Billing: A single payment method for all member accounts with combined usage for volume discounts • Hierarchical Account Structure: Organizational Units (OUs) to group accounts logically • Service Control Policies (SCPs): Centralized permission guardrails across accounts • Account Management: Programmatic account creation and invitation management • Integration Hub: Central point for enabling AWS services across the organization
Key Components
Management Account (formerly Master Account): The account that creates the organization and has full administrative control. This account pays for all charges accrued by member accounts and cannot have SCPs applied to restrict it.
Member Accounts: All other accounts within the organization. These can be created through Organizations or invited from existing standalone accounts.
Organizational Units (OUs): Containers for accounts that allow hierarchical organization. OUs can be nested up to five levels deep. Accounts can only belong to one OU at a time.
Root: The parent container for all accounts and OUs in your organization.
How AWS Organizations Works
1. Organization Structure When you create an organization, AWS creates a root container. You then create OUs to reflect your business structure (by environment, business unit, compliance requirement, or function). Accounts are placed into appropriate OUs.
2. Service Control Policies (SCPs) SCPs are JSON policy documents that specify maximum available permissions. Key characteristics: • SCPs do not grant permissions; they only restrict what IAM policies can grant • SCPs affect all users and roles in attached accounts, including the root user • SCPs do not affect the management account • SCPs use an inheritance model - policies attached to parent OUs flow down to child OUs and accounts • An explicit deny in an SCP overrides any allow
3. Policy Inheritance Policies are inherited from parent to child in the hierarchy. The effective permissions for an account are the intersection of all SCPs from the root down through the OU hierarchy to that account. This creates a permissions boundary.
4. Feature Sets Organizations offers two feature sets: • Consolidated Billing Only: Basic billing aggregation • All Features: Full functionality including SCPs, tag policies, AI services opt-out policies, and backup policies
Common Architectural Patterns
Multi-Account Strategy: • Security/Audit accounts for centralized logging and security tooling • Shared Services accounts for common infrastructure • Sandbox accounts for experimentation • Development, Staging, Production account separation • Network hub accounts for centralized networking
SCP Use Cases: • Restrict regions where resources can be deployed • Prevent accounts from leaving the organization • Enforce encryption requirements • Restrict which services can be used • Protect critical resources from deletion
Integration with Other Services
AWS Organizations integrates with numerous services for organization-wide management: • AWS Control Tower: Automated landing zone setup with guardrails • AWS CloudTrail: Organization trails for centralized logging • AWS Config: Organization-wide rules and aggregators • AWS RAM: Resource sharing across accounts • AWS SSO/IAM Identity Center: Centralized access management • AWS Service Catalog: Portfolio sharing across organization • AWS Backup: Organization-wide backup policies
Exam Tips: Answering Questions on AWS Organizations
Tip 1: Understand SCP Behavior Remember that SCPs are permission boundaries, not permission grants. If a question asks about granting access, SCPs alone cannot do this. Users still need IAM policies that grant permissions within the boundaries set by SCPs.
Tip 2: Management Account Exception The management account is never affected by SCPs. If a question involves restricting the management account, SCPs will not work. You would need to use IAM policies within that account.
Tip 3: Deny Always Wins In questions involving policy evaluation, explicit denies in SCPs override all allows. This follows the standard AWS policy evaluation logic.
Tip 4: Account Movement Considerations When moving accounts between OUs, the account inherits the new OU's policies. Questions may test understanding of how permissions change during account migration.
Tip 5: Consolidated Billing Benefits Look for scenarios mentioning Reserved Instance sharing or volume discounts across accounts - Organizations enables these through consolidated billing.
Tip 6: OU Design Questions When asked about OU structure, consider separation by: compliance requirements, environment lifecycle, business unit autonomy, and security classification.
Tip 7: Delegated Administrator Some AWS services support delegating administrative capabilities to a member account. This is preferred over using the management account for day-to-day operations.
Tip 8: Account Factory Questions about automated account provisioning often involve Organizations API combined with AWS Control Tower Account Factory or custom solutions using Step Functions and Lambda.
Tip 9: Cross-Account Access Patterns Distinguish between: IAM roles for cross-account access, AWS RAM for resource sharing, and Organizations for policy/governance. Each serves different purposes.
Tip 10: Leaving an Organization Member accounts leaving an organization become standalone accounts and must have valid payment methods. SCPs preventing this action are a common security pattern.