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MS SQL v2 sensor has stopped working



We have just upgraded from to and out SQL sensors have stopped working - actually all except one.

We have sensors added for our two SQL servers (2008 R2) that run a small SQL script, and they were all working perfectly until we upgraded. On one server we simply get "Timeout PE018" (single instance, multiple databases), but on the other server (multiple instances, multiple databases), one instance is working, the others all fail with messages similar to "Cannot open database "Holdiary" requested by the login. The login failed. Login failed for user 'redacted'.(Connectionstring: Data Source=redacted,1433;Initial Catalog=Holdiary;Integrated Security=True;Password=)".

With a colleague we have discovered the reason, only one instance is on port 1433, the others are dynamic - the sensor is now only using the fixed port for all the instances, so in the last example above it always connects to the same instance regardless of what we define in the sensor and therefore fails. Before the upgrade the sensor was connecting correctly, now it doesn't.

How can we fix this?

sql-server sql-server-login sqlsensor

Created on May 15, 2015 9:03:34 AM

3 Replies



Have you tried to use apexes in the connection string? Data Source='redacted,1433';Initial Catalog=Holdiary;Integrated Security=True;Password=

Created on Jun 30, 2016 3:31:52 PM



No, because at some point later on, PRTG got fixed and the sensors started working again.

Created on Jul 1, 2016 8:45:15 AM



Alright, thanks for the update, Fernando!

Created on Jul 1, 2016 9:12:56 AM by  Stephan Linke [Paessler Support]

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