Azure Documentation

Troubleshooting Azure Identity

This guide provides common troubleshooting steps and solutions for issues related to Azure Identity services, including Azure Active Directory (now Microsoft Entra ID), managed identities, and service principals.

Common Issues and Solutions

1. Authentication Failures

Symptom: Users or applications are unable to authenticate to Azure resources.

  • Check Credentials: Ensure that the username, password, or client secret is correct. For service principals, verify that the secret has not expired or been revoked.
  • Token Expiration: Tokens have a limited lifespan. Applications might need to refresh their tokens periodically.
  • Permissions: Verify that the identity (user, managed identity, or service principal) has the necessary role assignments and permissions on the target Azure resource.
  • Conditional Access Policies: Review any active Conditional Access policies in Microsoft Entra ID that might be blocking access based on location, device state, or sign-in risk.
  • Multi-Factor Authentication (MFA): If MFA is required, ensure the user is prompted and successfully completing the MFA challenge.

2. Authorization Denied Errors (HTTP 403)

Symptom: An operation is attempted, but the identity lacks the required permissions.

  • Role Assignments: Confirm that the identity has been assigned an appropriate role (e.g., "Reader", "Contributor") at the correct scope (subscription, resource group, or resource).
  • RBAC Propagation: Role assignments can take a few minutes to propagate. If the assignment was recently made, wait a short period and try again.
  • Resource Provider Registration: Ensure the resource provider for the service you are trying to access is registered for the subscription.
Tip: Use the Azure portal's "Access control (IAM)" blade to review and manage role assignments for a resource or resource group.

3. Managed Identity Issues

Symptom: A resource configured with a managed identity cannot access other Azure services.

  • System-Assigned vs. User-Assigned: Ensure the correct type of managed identity is used and enabled. For system-assigned, it's tied to the lifecycle of the resource. For user-assigned, it's a standalone resource.
  • Granting Permissions: The managed identity's principal needs to be granted permissions on the target resource (e.g., granting the managed identity "Storage Blob Data Reader" role on a storage account).
  • Resource Identity Status: For system-assigned managed identities, verify that the "Identity" section of the resource in the Azure portal shows "System assigned: Enabled".

4. Service Principal Credential Problems

Symptom: Applications using service principals fail to authenticate.

  • Secret Expiration: Service principal secrets have an expiration date. Ensure the secret is renewed before it expires.
  • Certificate Expiration: If using certificate-based authentication for a service principal, ensure the certificate has not expired and is correctly configured.
  • App Registration Details: Verify that the Application (client) ID and Directory (tenant) ID are correctly configured in your application's settings.
  • Scope of Permissions: Ensure the service principal has the necessary API permissions granted in its App Registration in Microsoft Entra ID, and that the application has been granted consent.
Warning: Never hardcode service principal secrets or certificates directly in your application code. Use secure methods like Azure Key Vault.

5. Diagnosing with Azure Monitor and Logs

Symptom: Unclear error messages or intermittent issues.

  • Microsoft Entra ID Sign-in Logs: These logs provide detailed information about sign-in attempts, including success/failure status, authentication methods, and any applied Conditional Access policies. Access them via Microsoft Entra ID -> Monitoring & health -> Sign-in logs.
  • Azure Activity Logs: Monitor the Activity Log for operations related to identity management, such as role assignments or policy changes.
  • Resource-Specific Diagnostic Logs: Some Azure services offer their own diagnostic logs that can provide insights into authentication and authorization events.

Advanced Troubleshooting

Service Principal vs. Managed Identity

Understand when to use each:

  • Managed Identities: Recommended for Azure resources (VMs, App Services, Functions) that need to authenticate to other Azure services. Simplifies credential management.
  • Service Principals: Used for applications, scripts, or services running outside of Azure or when more control over authentication is needed.

Troubleshooting Graph API Access

If your application uses Microsoft Graph:

  • Correct Permissions: Ensure the service principal or managed identity has been granted the necessary delegated or application permissions in the Microsoft Entra ID App Registration for Microsoft Graph.
  • Token Scopes: Verify that the access token requested has the correct scopes (permissions) for the Graph API endpoints you are trying to access.

For persistent issues, consider opening a support ticket with Azure, providing detailed logs and context.