Security Best Practices for Azure SQL Database

Protecting your data in Azure SQL Database requires a layered approach that combines network controls, identity management, encryption, monitoring, and incident response. This guide outlines the essential practices you should implement to secure your workloads.

1. Network Security

Use Virtual Network Service Endpoints or Private Link to restrict access to your database from specific subnets.
Configure firewall rules to allow only trusted IP ranges.
Leverage Azure DDoS Protection for large‑scale attacks.

2. Authentication & Authorization

Prefer Azure AD authentication over SQL authentication.
Implement role‑based access control (RBAC) to grant the least privileges.
Enable multi‑factor authentication (MFA) for privileged accounts.

Enable Azure AD Authentication

CREATE USER [john.doe@contoso.com] FROM EXTERNAL PROVIDER;
ALTER ROLE db_datareader ADD MEMBER [john.doe@contoso.com];

3. Data Encryption

Transparent Data Encryption (TDE) is enabled by default – verify it’s active.
For highly sensitive data, use Always Encrypted with secure enclaves.
Encrypt backups using Storage‑account encryption or client‑side encryption.

Verify TDE Status

SELECT encryption_state, algorithm_desc FROM sys.dm_database_encryption_keys;

4. Threat Detection & Vulnerability Assessment

Turn on Advanced Threat Protection (ATP) for real‑time alerts.
Schedule Vulnerability Assessment scans and review findings weekly.

Enable Advanced Threat Protection

az sql db threat-policy update \
  --resource-group MyResourceGroup \
  --server myserver \
  --name mydb \
  --state Enabled \
  --email-account-admins true

5. Backup & Recovery

Use geo‑redundant backup storage for disaster recovery.
Test point‑in‑time restore (PITR) regularly.

6. Monitoring & Auditing

Enable SQL Auditing to Log to Azure Monitor or a Log Analytics workspace.
Set up alerts for suspicious login attempts and permission changes.

Configure Auditing to Log Analytics

az sql db audit-policy update \
  --resource-group MyResourceGroup \
  --server myserver \
  --name mydb \
  --state Enabled \
  --storage-account myauditstorage \
  --log-analytics-workspace /subscriptions/xxxx/resourceGroups/MyRG/providers/Microsoft.OperationalInsights/workspaces/MyWorkspace

7. Compliance

Map security controls to standards (ISO 27001, SOC 2, PCI‑DSS) using Azure Policy.
Maintain documentation of configurations and review changes via Azure Change Tracking.