Quick Tip- Azure SQL Server Connectivity
Troubleshooting connectivity between application and database servers in Azure.
- An application server in Azure can’t connect to an IaaS SQL Server on Windows (also in Azure).
- The Connection Troubleshoot utility in the Azure Portal says network connectivity between the App server and SQL server on port 1433 is allowed:
Test-NetConnectionon the App server shows that communication with the SQL Server is blocked on port 1433
Windows Firewall on the SQL Server is blocking communications from the App Server
Add a rule to the Windows Firewall on the SQL Server to allow SQL Traffic. See Microsoft Docs for details on how to do this.