how can i set up an azure virtual machine running sql server to allow connection from the internet

Hi Angel Garcia
Based on your description, it sounds like you've already addressed several of the key configuration points—enabling TCP/IP and shared memory, setting up the NSG to permit traffic to your SQL Server port, and creating a SQL login. One commonly overlooked piece in these scenarios is the local Windows Firewall on the virtual machine itself.

Here are the steps to verify and address potential issues:

1. Windows Firewall Configuration: Even though the NSG rule allows traffic from the specified IP address, the Windows Firewall inside the VM can still block incoming connections. Open Windows Defender Firewall with Advanced Security on your VM and confirm there’s an inbound rule that explicitly allows traffic on the SQL Server port (often 1433) from the single IP address you want to permit. If not, create a new custom inbound rule:
   • Rule Type: Port
   • Protocol: TCP
   • Specific local ports: Specify the SQL Server port (e.g., 1433, or your custom port)
   • Scope: Under “Remote IP address,” add the single IP address that’s allowed
   • Action: Allow the connection
   • Profile: Apply as needed (Domain, Private, Public)
   • Name: Give the rule a descriptive name.
2. SQL Server Configuration: Confirm that SQL Server is indeed listening on the port that you expect. Open SQL Server Configuration Manager, go to SQL Server Network Configuration, and double-check the TCP/IP properties (e.g., the IPAll section should have your desired TCP port set properly). For named instances, ensure you’ve either set a static port or enabled the SQL Server Browser service.
3. Remote Connections Setting: Verify that SQL Server is set up to allow remote connections. You can check this by opening SQL Server Management Studio (SSMS), right-clicking on the server, choosing Properties, then Connections, and making sure Allow remote connections to this server is enabled.
4. Testing the Connection: After confirming these settings, use a tool like telnet or PowerShell (e.g., Test-NetConnection -ComputerName <Your_VM_Public_IP> -Port <SQL_Port>) from the allowed IP to verify that the TCP port can be reached. This can help isolate whether the issue is network-related or within SQL Server itself.

By ensuring the Windows Firewall on the VM has a rule permitting the connection from that single IP, you should be able to resolve the connectivity issue. Although the NSG is correctly configured in Azure’s virtual network layer, the VM’s internal firewall often needs its own rule to grant access.

I hope this helps clarify what might be missing in your configuration. If you have any more details about whether you’re using a named instance or if you encounter further issues after these changes, feel free to share.

Additional Tips:

• If you’re running a named instance, remember that it may not automatically listen on the default 1433 port. In that case, assign a fixed port or ensure the SQL Server Browser service is running.
• Check the SQL Server error logs to see if there are any connection error messages that might provide further clues.
• For extra security, consider also applying logging on the firewall or NSG to monitor whether connection requests are being dropped.

These extra steps might give you further insights into any intermittent network issues or misconfigurations.

thank you!! will look into all this

Hi @ Angel Garcia

Could you provide an update on this, please?

it does seem to be a problem with the windows firewall. we are still working on creating the rule to open it. will report back in day or 2

Angel Garcia

Sure, Thankyou.