Secrets Manager Best Practices
Why Secrets Manager Best Practices Matter
AWS Secrets Manager is a critical service for securing sensitive information such as database credentials, API keys, and other secrets. Understanding best practices is essential for the AWS Solutions Architect Professional exam because improper secrets management can lead to security breaches, compliance violations, and operational failures. Questions on this topic test your ability to design secure, scalable, and cost-effective solutions.
What is AWS Secrets Manager?
AWS Secrets Manager is a managed service that helps you protect access to your applications, services, and IT resources. It enables you to:
- Store and retrieve secrets securely
- Rotate secrets automatically
- Control access using fine-grained IAM policies
- Audit secret usage through AWS CloudTrail
- Replicate secrets across multiple regions
Key Best Practices
1. Enable Automatic Rotation
Configure automatic rotation for all secrets, especially database credentials. Use Lambda functions to implement custom rotation logic when needed. Set rotation schedules based on your security requirements (typically 30-90 days).
2. Use Fine-Grained IAM Policies
Apply the principle of least privilege. Grant access to specific secrets rather than broad permissions. Use resource-based policies in combination with identity-based policies for cross-account access.
3. Implement Secret Versioning
Leverage staging labels (AWSCURRENT, AWSPREVIOUS, AWSPENDING) to manage secret versions during rotation. This ensures applications can fall back to previous versions if issues occur.
4. Enable Multi-Region Replication
For disaster recovery and high availability, replicate secrets to secondary regions. This ensures applications in multiple regions can access secrets with low latency.
5. Use VPC Endpoints
Create VPC endpoints for Secrets Manager to keep traffic within the AWS network. This improves security by avoiding exposure to the public internet.
6. Encrypt with Customer Managed KMS Keys
While Secrets Manager uses AWS managed keys by default, use customer managed KMS keys for enhanced control over encryption and to meet compliance requirements.
7. Monitor and Audit
Enable CloudTrail logging to track all API calls to Secrets Manager. Set up CloudWatch alarms for suspicious activities such as failed access attempts or unusual retrieval patterns.
8. Cache Secrets in Applications
Use the Secrets Manager caching libraries to reduce API calls and improve application performance. Implement appropriate cache invalidation strategies.
How It Works
When an application needs a secret:
1. The application calls the Secrets Manager API (GetSecretValue)
2. IAM validates the request against policies
3. Secrets Manager retrieves the encrypted secret from storage
4. KMS decrypts the secret
5. The plaintext secret is returned to the application over TLS
During rotation:
1. Secrets Manager invokes the rotation Lambda function
2. The Lambda creates a new secret version with AWSPENDING label
3. The Lambda updates the target service with new credentials
4. The Lambda tests the new credentials
5. The Lambda moves labels (AWSPENDING becomes AWSCURRENT)
Exam Tips: Answering Questions on Secrets Manager Best Practices
Tip 1: When questions mention hardcoded credentials or credentials stored in application code, Secrets Manager is typically the correct answer for remediation.
Tip 2: For cross-account secret sharing scenarios, look for answers involving resource-based policies combined with IAM roles.
Tip 3: If a question asks about reducing costs while maintaining security, consider that Secrets Manager charges per secret per month and per API call. Caching can help reduce API costs.
Tip 4: Compare Secrets Manager with Parameter Store. Secrets Manager is preferred when automatic rotation is required, especially for RDS, Redshift, and DocumentDB credentials.
Tip 5: For disaster recovery scenarios, multi-region secret replication is the key feature to look for in answer options.
Tip 6: Questions about compliance and audit trails should point you toward CloudTrail integration and KMS customer managed keys.
Tip 7: When Lambda functions need database credentials, the best practice is to retrieve secrets at function initialization and cache them, not on every invocation.
Tip 8: For hybrid environments, remember that on-premises applications can access Secrets Manager through AWS PrivateLink or by using IAM roles with STS.