You cannot directly connect the Amazon Redshift ODBC driver to Azure Entra ID (formerly Azure AD) for single sign-on because Redshift does not support Azure as an identity provider. The native authentication mechanism relies on IAM database authentication, which uses AWS credentials, or standard username/password combinations. To achieve SSO, you must configure a reverse proxy or use AWS IAM Identity Center with role assumption.
Understanding the Authentication Gap
The confusion often arises from the similarity between Microsoft Entra ID and AWS IAM Identity Center. While both provide enterprise identity management, they operate on different protocols and trust models. The Amazon Redshift ODBC driver is designed to speak directly with the Redshift data warehouse using either:
- Standard Authentication: A static username and password stored in the connection string or keychain.
- IAM Database Authentication: Temporary security tokens generated via AWS Security Token Service (STS) when the user assumes an IAM role.
Azure Entra ID issues JWTs or SAML tokens that the Redshift endpoint does not understand natively. Attempting to force this integration by modifying ODBC configuration files will result in connection failures. There is no setting in the odbc.ini file that accepts Azure credentials for direct Redshift access.
Recommended Architecture: IAM Role Assumption
The most robust way to manage access without storing passwords is to use AWS IAM Database Authentication. This allows users to authenticate using their existing corporate credentials through a federated identity provider that AWS supports, such as Okta, PingIdentity, or even Azure AD if configured correctly via AWS IAM Identity Center (though this requires specific setup).
For pure Azure environments, the standard pattern involves an application layer or a gateway service. This service handles the Azure SSO flow, obtains an Azure token, exchanges it for AWS STS temporary credentials, and then passes those credentials to the client. The client then uses these temporary AWS credentials to connect to Redshift via ODBC.
Step 1: Configure IAM Database Authentication
First, enable IAM database authentication in your Redshift cluster. Navigate to the AWS Console, select your cluster, and choose "Modify." Ensure that "IAM database authentication" is enabled. You must also create an IAM policy that grants permission to connect to the specific database and attach it to the IAM role your users will assume.
Step 2: Set Up the AWS CLI or SDK
Your users need the AWS CLI or an SDK configured with their IAM permissions. When connecting via ODBC, the driver can accept temporary credentials. You do not need to hardcode these. Instead, the application connecting to Redshift should call sts:AssumeRole to get a session token.
Alternative: Using a Reverse Proxy or Gateway
If you require true SSO where the user logs into Azure and then seamlessly accesses Redshift without managing AWS keys, you need an intermediary. Tools like Azure App Proxy can sometimes be adapted, but for data warehouses, a dedicated SQL gateway is preferred.
This gateway sits between the user and Redshift. It performs the Azure AD authentication, validates the user's group membership, and then generates the necessary AWS STS credentials on the backend. The ODBC connection string points to the gateway, not Redshift directly. The gateway injects the valid AWS credentials into the session before forwarding the query.
Configuring the ODBC Driver
Once you have valid AWS credentials (Access Key, Secret Key, and Session Token), configuring the Redshift ODBC driver is straightforward. In your odbc.ini or connection settings, specify the following parameters:
- Servers: Your Redshift cluster endpoint.
- Port: Typically 5439.
- Username: The IAM role ARN or a placeholder name.
- Password: The temporary session token.
Ensure that the driver version is up to date to support IAM authentication properly. Older versions may not handle the token expiration and refresh cycles correctly.
Common Pitfalls and Troubleshooting
Even with the correct architecture, errors can occur. One common issue is related to SSL certificates when the gateway communicates with AWS services. If you encounter certificate verification errors, ensure that your system trusts the AWS CA bundle. This is similar to issues seen in other cloud integrations, such as SSL certificate verification failures in Docker containers.
Another frequent problem is network connectivity. Ensure that the security groups attached to your Redshift cluster allow inbound traffic from the IP addresses of your gateway or proxy server. Do not open ports to 0.0.0.0/0 unless absolutely necessary for testing.
Finally, verify that the IAM role has the correct permissions. The policy must explicitly allow redshift:GetClusterCredentials. Without this specific API call permission, the IAM database authentication will fail silently or return generic authentication errors.
Frequently Asked Questions
Can I use Azure AD directly as the IdP for Redshift?
No, Amazon Redshift does not support Azure AD as a native identity provider for direct ODBC connections. You must use AWS IAM Database Authentication or a third-party gateway that translates Azure tokens into AWS credentials.
What happens if my AWS temporary credentials expire during a session?
The Redshift ODBC driver does not automatically refresh temporary credentials. If the session token expires, the connection will drop. Your application or gateway must implement logic to detect this error and re-assume the IAM role to obtain new credentials.
Is IAM Database Authentication slower than password authentication?
The initial connection may take slightly longer due to the STS token generation, but subsequent queries are not affected. The performance difference is negligible for most analytical workloads compared to the security benefits.
How do I manage user permissions if I use IAM roles?
User permissions in Redshift are managed via SQL GRANT statements. However, you assign these grants based on the IAM role ARN rather than a traditional database username. This means all users assuming that role share the same database privileges.
Can I use Azure AD Connect to sync users to AWS?
Azure AD Connect synchronizes identities to Azure AD, not AWS. To synchronize identities to AWS, you should use AWS IAM Identity Center or a third-party identity governance tool that supports SCIM provisioning to AWS.