AWS Control Tower vs. Organizations: Which One Should You Use to Manage 100+ Accounts?
Managing a large number of AWS accounts (we’re talking 100+) can quickly become complex. You need consistent security, efficient resource management, and centralized governance. Luckily, AWS offers two powerful services to help: AWS Control Tower and AWS Organizations.
But which one should you choose when you’re dealing with a significant number of accounts? Let’s break down each service and see which fits your needs best.
What is AWS Organizations?
Think of AWS Organizations as the foundation for managing multiple AWS accounts. It allows you to:
- Centrally manage and govern your accounts: You can create an organizational structure (like a tree) with a root account and multiple member accounts.
- Consolidated billing: Pay for all your accounts through a single payment method.
- Apply Service Control Policies (SCPs): These policies allow you to centrally control the AWS services and actions that are allowed in your member accounts. This is crucial for enforcing security and compliance across your organization.
- Share resources: Easily share resources like VPCs, subnets, and secrets across your accounts.
In simple terms: AWS Organizations gives you the basic tools to group and manage your AWS accounts and set broad rules for them.
What is AWS Control Tower?
AWS Control Tower builds on top of AWS Organizations. It provides a higher-level, more automated way to set up and govern a multi-account AWS environment. Think of it as a pre-configured and opinionated solution for establishing a secure and compliant baseline.
Here’s what Control Tower offers:
- Automated Landing Zone setup: Control Tower automatically sets up a well-architected, secure, multi-account environment (your “landing zone”) based on AWS best practices. This includes configuring essential services like AWS Organizations, AWS IAM Identity Center (for single sign-on), AWS CloudTrail (for centralized logging), and AWS Config (for resource configuration tracking).
- Guardrails: Control Tower implements preventative and detective controls (called “guardrails”) to enforce security, compliance, and cost management policies across your accounts. These guardrails are predefined and help prevent common misconfigurations.
- Account Factory: Easily provision new, pre-configured AWS accounts that automatically inherit the security and compliance controls defined in your landing zone.
- Centralized Dashboard: Provides a single view of your multi-account environment, showing the status of your landing zone and any policy violations.
In simple terms: AWS Control Tower automates the complex process of setting up a secure and well-governed multi-account environment, offering built-in best practices and ongoing enforcement.
AWS Control Tower vs. Organizations: Key Differences
| Feature | AWS Organizations | AWS Control Tower |
|---|---|---|
| Core Function | Foundational service for multi-account management | Automated setup and governance of a multi-account environment |
| Setup Complexity | Requires manual configuration of many services | Automated landing zone setup |
| Best Practices | Requires you to implement your own best practices | Enforces predefined AWS best practices through guardrails |
| Automation | Limited automation | High level of automation for setup and governance |
| Guardrails | Requires manual creation and application of SCPs | Predefined and automated guardrails |
| Account Provisioning | Manual account creation within Organizations | Automated account provisioning with Account Factory |
| Single Sign-On | Requires separate configuration of IAM Identity Center | Integrated with IAM Identity Center during landing zone setup |
| Centralized Logging & Auditing | Requires manual configuration of CloudTrail & Config | Automatically configured during landing zone setup |
| Complexity Management (100+ accounts) | Can become complex to manage manually | Significantly simplifies management through automation |
| Cost | No additional cost beyond the underlying services | No additional cost beyond the underlying services |
Which One Should You Use for 100+ Accounts?
For managing 100+ AWS accounts, AWS Control Tower is generally the recommended choice, especially if:
- You need to quickly establish a secure and compliant multi-account environment: Control Tower’s automated landing zone setup saves significant time and effort.
- You want to enforce consistent security and governance policies across all your accounts: The predefined and automated guardrails help ensure adherence to best practices.
- You need a streamlined process for provisioning new accounts: The Account Factory makes it easy to create pre-configured, compliant accounts.
- You lack deep expertise in setting up and configuring a secure multi-account environment from scratch: Control Tower provides an opinionated and well-architected solution.
However, AWS Organizations is still essential and forms the foundation for Control Tower. You cannot use Control Tower without AWS Organizations.
When might you primarily use AWS Organizations (without Control Tower) for a large number of accounts?
- You have highly customized and complex requirements that don’t align with Control Tower’s prescriptive nature: If you need granular control over every aspect of your multi-account setup and Control Tower’s guardrails are too restrictive.
- You have already established a mature and well-governed multi-account environment using Organizations: Migrating to Control Tower might involve significant effort and disruption.
- You have very specific compliance needs that require manual configuration beyond Control Tower’s capabilities.
In summary:
- For most organizations managing 100+ accounts, starting with or migrating to AWS Control Tower is the most efficient and effective way to establish and maintain a secure and well-governed multi-account environment. It leverages the power of AWS Organizations while adding a layer of automation and best-practice enforcement.
- AWS Organizations provides the fundamental building blocks for multi-account management, and it’s always a prerequisite for using Control Tower.
By understanding the strengths of both AWS Control Tower and Organizations, you can make an informed decision that best suits your organization’s needs for managing a large and complex AWS environment.