Secure app configuration using Azure App Configuration or Key Vault
5 minutes
5 Questions
Azure App Configuration and Azure Key Vault are two essential services for securing application configuration data in Azure environments. Azure App Configuration provides a centralized service for managing application settings and feature flags. It allows developers to store non-sensitive configura…Azure App Configuration and Azure Key Vault are two essential services for securing application configuration data in Azure environments. Azure App Configuration provides a centralized service for managing application settings and feature flags. It allows developers to store non-sensitive configuration data separately from code, enabling dynamic configuration updates across multiple applications and environments. This service supports hierarchical namespaces, labels for environment-specific settings, and integration with managed identities for secure access. Key features include point-in-time snapshots, automatic refresh capabilities, and native integration with popular frameworks like .NET, Java, and JavaScript. Azure Key Vault, on the other hand, is specifically designed for storing sensitive information such as secrets, encryption keys, and certificates. It provides hardware security module (HSM) backed storage, ensuring cryptographic keys never leave the security boundary. Key Vault offers granular access control through Azure RBAC and access policies, comprehensive audit logging, and automatic secret rotation capabilities. When implementing secure app configuration, best practices include using managed identities to authenticate applications to both services, eliminating the need for storing credentials in code. Developers should reference Key Vault secrets from App Configuration using Key Vault references, creating a unified configuration experience while maintaining security boundaries. This pattern allows applications to retrieve all configuration from App Configuration while sensitive values are automatically fetched from Key Vault. Additionally, implementing proper access controls using Azure RBAC ensures least-privilege access. Enabling soft-delete and purge protection on Key Vault prevents accidental data loss. Using private endpoints restricts network access to these services, enhancing security posture. Regular rotation of secrets and keys, combined with versioning support, ensures applications remain secure over time while maintaining availability during transitions.
Secure App Configuration using Azure App Configuration or Key Vault
Why It Is Important
Securing application configuration is critical for protecting sensitive data such as connection strings, API keys, certificates, and secrets. Hardcoding secrets in application code or configuration files poses significant security risks including data breaches and unauthorized access. Azure provides robust services to centralize, manage, and secure these configurations, which is essential knowledge for the AZ-204 exam.
What It Is
Azure Key Vault is a cloud service designed to safeguard cryptographic keys, secrets, and certificates. It provides: - Secrets management for storing tokens, passwords, and API keys - Key management for encryption keys - Certificate management for SSL/TLS certificates - Hardware Security Module (HSM) backed storage
Azure App Configuration is a service for centrally managing application settings and feature flags. It provides: - Centralized configuration management - Feature flag management - Dynamic configuration updates - Integration with Key Vault for secret references
How It Works
Azure Key Vault: 1. Create a Key Vault in your Azure subscription 2. Add secrets, keys, or certificates to the vault 3. Configure access policies or use Azure RBAC for authorization 4. Applications authenticate using Managed Identity (recommended) or service principals 5. Retrieve secrets programmatically using the Azure SDK
Azure App Configuration: 1. Create an App Configuration store 2. Add key-value pairs for settings 3. Use Key Vault references for sensitive values 4. Connect your application using connection strings or Managed Identity 5. Implement dynamic refresh to pull updated configurations
Key Integration Pattern: App Configuration stores non-sensitive settings and references to Key Vault secrets. When your app reads a Key Vault reference from App Configuration, it automatically retrieves the actual secret from Key Vault.
Authentication Methods: - Managed Identity: Preferred method, eliminates credential management - Service Principal: Uses client ID and secret/certificate - Access Tokens: For scenarios requiring explicit token handling
Exam Tips: Answering Questions on Secure App Configuration
1. Managed Identity is the preferred authentication method - When asked about the most secure way to access Key Vault, choose Managed Identity over connection strings or service principals with secrets.
3. Access Policies vs Azure RBAC: Understand that Key Vault supports both models. RBAC provides more granular control and is the modern approach.
4. Soft Delete and Purge Protection: These features protect against accidental or malicious deletion. Know that purge protection prevents permanent deletion during the retention period.
5. Key Vault References in App Configuration: Questions may test whether you understand that App Configuration can reference Key Vault secrets using a special URI format.
6. Secret Versioning: Key Vault maintains versions of secrets. Applications can reference specific versions or always get the latest.
7. Common SDK Classes: - SecretClient for secrets - KeyClient for keys - CertificateClient for certificates - ConfigurationClient for App Configuration
8. Watch for scenario-based questions: If the question mentions storing connection strings, passwords, or API keys, the answer typically involves Key Vault. If it mentions feature flags or application settings, think App Configuration.
9. Network Security: Know that Key Vault supports private endpoints and firewall rules for network isolation.
10. Rotation and Expiration: Understand that Key Vault supports automatic key rotation and secret expiration notifications through Event Grid integration.