Secure Your Azure SQL Managed Instance
Tip: Security is a continuous process. Regularly review and update your security configurations.
This tutorial guides you through the essential steps to secure your Azure SQL Managed Instance, ensuring your data is protected against unauthorized access and potential threats.
1. Configure Network Security
Network security is the first line of defense. Azure SQL Managed Instance resides within an Azure Virtual Network (VNet), providing isolation and control over network traffic.
1.1. Network Security Groups (NSGs)
Use Network Security Groups to filter network traffic to and from Azure resources in an Azure VNet. For SQL Managed Instance, you'll typically configure inbound rules to allow traffic on port 1433 (the default SQL Server port) from specific IP addresses or subnets.
Best Practice: Restrict inbound access to only the necessary sources. Avoid opening port 1433 to the internet.
1.2. Private Endpoints
For enhanced security, use Private Endpoints to establish a secure connection to your SQL Managed Instance directly from your VNet, without exposing it to the public internet. This ensures all traffic travels over the Microsoft backbone network.
2. Implement Authentication and Authorization
Controlling who can access your instance and what they can do is critical.
2.1. SQL Authentication vs. Azure AD Authentication
While SQL authentication is available, leveraging Azure Active Directory (Azure AD) authentication is highly recommended for centralized identity management and security.
- Azure AD Authentication: Allows you to manage users and permissions through Azure AD, enabling features like multi-factor authentication (MFA) and conditional access policies.
- SQL Authentication: Uses username and password. Ensure strong password policies are enforced.
2.2. Role-Based Access Control (RBAC)
Assign granular permissions to users and groups using RBAC. This principle of least privilege ensures that users only have the access they need to perform their tasks.
Steps:
- Navigate to your SQL Managed Instance in the Azure portal.
- Go to "Access control (IAM)".
- Click "Add" and select an appropriate role (e.g., Contributor, Reader, SQL DB Contributor).
- Assign the role to the desired user, group, or service principal.
3. Encrypt Data at Rest and in Transit
Protecting your data, even if it's accessed without authorization, is paramount.
3.1. Transparent Data Encryption (TDE)
TDE encrypts your SQL Server data files, log files, and backups at rest. Azure SQL Managed Instance enables TDE by default, using a service-managed key. You can optionally use your own key from Azure Key Vault for greater control.
Note: TDE is enabled by default for newly created SQL Managed Instances.
3.2. TLS/SSL Encryption
Ensure that connections to your SQL Managed Instance are encrypted using Transport Layer Security (TLS). By default, SQL Managed Instance enforces TLS 1.2 for all incoming connections.
Verification:
You can verify the TLS version used by your client application when connecting. Ensure your client drivers support and are configured to use TLS 1.2.
4. Auditing and Threat Detection
Monitor and detect potential threats to your database.
4.1. SQL Auditing
Configure SQL Auditing to track database events and write them to an audit log in Azure Blob Storage, Azure Log Analytics, or Azure Event Hubs. This helps in maintaining regulatory compliance and understanding database activity.
Key Events to Audit:
- Logins and Logouts
- Data Modifications (INSERT, UPDATE, DELETE)
- Schema Changes
- Permissions Changes
4.2. Microsoft Defender for SQL
Microsoft Defender for SQL provides advanced threat protection capabilities, including vulnerability assessment and advanced threat detection. It helps identify and mitigate potential database threats.
Enable Defender for SQL:
- Navigate to your SQL Managed Instance in the Azure portal.
- Under "Security", select "Microsoft Defender for Cloud".
- Enable "SQL advanced threat protection".
5. Manage Secrets and Credentials
Securely manage sensitive information like connection strings and passwords.
5.1. Azure Key Vault Integration
Store and manage your SQL Managed Instance credentials, certificates, and other secrets in Azure Key Vault. This avoids embedding sensitive information directly in your applications or code.
Conclusion
By implementing these security measures, you can significantly enhance the security posture of your Azure SQL Managed Instance, safeguarding your valuable data.