Please could you assist with Microsoft SQL error 53

Question

Hi

Could you please assist with SQL error 53? We have two environments (AWS and OneCloud), so we cannot access the One Cloud environment via SSMS that is running on AWS, because of SQL error 53, but we can remote into the One Cloud environment. Could we please get assistance with the error resolutions?

We upgraded the One Cloud environment from SQL Server 2016 to 2022, and that is when we experienced the error connecting from AWS to One Cloud. However, both environments are using SSMS 20.2 versions.

Answer 1

SELECT * FROM sys.messages WHERE message_id = 53

returns no rows. That is, there is no error message 53 from SQL Server.

It would have helped if you had included the full error message, but the number 53 seems familiar. Some client APIs cite this number when they cannot connect to the SQL Server instance you have specified.

Reasons for this includes:

• Server and/or instance name misspelled.
• SQL Server is not running.
• Browser service is not running.
• Blocking firewalls.

The list is not exhaustive.

It seems that in your case, you get the issue in specific cloud environments. It is quite likely that your problems are related to configuration in these environments, and you should probably inquire with these cloud operators, for instance by opening a support case.

Answer 2

Error 53 in SQL Server typically indicates that the server was not found or was not accessible. Here are some steps you can take to troubleshoot and resolve this issue:

1. Verify Instance Name: Ensure that the instance name you are using to connect to the One Cloud environment is correct. If you are using a named instance, make sure to specify it correctly in the connection string.
2. Check SQL Server Configuration: Confirm that SQL Server is configured to allow remote connections. This can be checked in the SQL Server Configuration Manager under the SQL Server Network Configuration settings.
3. Firewall Settings: Ensure that the firewall on the One Cloud environment is configured to allow inbound connections on the SQL Server port (default is 1433 for TCP/IP). If you upgraded to SQL Server 2022, check if any new firewall rules need to be applied.
4. Network Issues: Since you can remote into the One Cloud environment, check if there are any network issues that might be preventing access from the AWS environment. This includes checking DNS settings and ensuring that the SQL Server's IP address is reachable from AWS.
5. SQL Server Services: Make sure that the SQL Server services are running properly on the One Cloud environment. You can check this through the SQL Server Configuration Manager or Services management console.
6. Error Logs: Review the SQL Server error logs for any additional information that might indicate why the connection is failing.

If you continue to experience issues after checking these items, you may want to consult the specific troubleshooting documentation for SQL Server connection errors.

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References:

• A network-related or instance-specific error occurred while establishing a connection to SQL Server
• Troubleshoot DMS errors when connecting to source databases