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Microsoft SQL v2 Sensor Issue "The semaphore timeout period has expired"




We have a SQL server cluster comprised of 2 servers, with various databases instances on.

- Microsoft Server 2016 - SSMS v 17.9.1 - SQL server v 13.0.5865.1

We are trying to add a Microsoft SQL v2 sensor to monitor a specific database in the cluster. Both SQL servers in the cluster reside in the same location as the core PRTG server

We have a local SQL user with RO permissions to the specific database, and the Microsoft SQL v2 sensor inherits the credential information from the SQL settings above.

When adding the sensor though, we get this error:

"A connection was successfully established with the server, but then an error occurred during the pre-login handshake. (provider: TCP Provider, error: 0 - The semaphore timeout period has expired.)"

My initial thinking was a connectivity issue between PRTG and the SQL cluster (firewall issue etc hence the semaphore message), but they are in the same location.

Do you have any suggestions for this error?

Many thanks

microsoft-sql-v2 prtg sql

Created on Apr 25, 2022 10:29:45 AM

1 Reply



Hello, we notice this error comes directly from SQL, it is not an error message from PRTG. From our perspective we would suggest to make sure the probe has .net framerwork version 4.7.2. And also we would need to see screenshots of the settings tab of this sensor. You can add the screenshots here or you could send an email to [email protected] with the information so we can take a look.

Created on Apr 28, 2022 11:36:30 PM by  Jonathan Mena [Paessler Technical Support]

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