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Could not create the sensor Exchange Mail Queue: DNS issue?




I have an Exchange server, which until recently was being monitored fine. Then two sensors went down over the weekend related to WinRM/Powershell and I'm struggling to resolve the issue. I deleted one sensor and tried to re-create it, but got this error:

The Sensor can not connect to the Device using Remote-PowerShell. Ensure that remote management is enabled on the Exchange Server and the user-name and password is correct. See https://kb.paessler.com/knowledgebase/en/topic/54353 for details. Connecting to remote server autodiscover.domain.co.uk failed with the following error message : WinRM cannot process the request. The following error occurred while using Kerberos authentication: The computer autodiscover.domain.co.uk is unknown to Kerberos. Verify that the computer exists on the network, that the name provided is spelled correctly, and that the Kerberos configuration for accessing the computer is correct. The most common Kerberos configuration issue is that an SPN with the format HTTP/autodiscover.domain.co.uk is not configured for the target. If Kerberos is not required, specify the Negotiate authentication mechanism and resubmit the operation. For more information, see the about_Remote_Troubleshooting Help topic.

I believe the problem is because PRTG is reporting an issue connecting to autodiscover.domain.co.uk, but the device object is exchangeserver.domain.co.uk

It seems the PRTG server is not resolving the device name correctly and trying to connect to the autodiscover IP.

The Exchange server has a separate IP addresses for autodiscover. Having double-checked DNS, both the forward and reverse lookups are all correct. And when I ping the names from the PRTG server, the correct IP's are returned. What could be going wrong?

dns-resolution powershell winrm

Created on Nov 5, 2018 8:58:15 AM

2 Replies



Hi there,

We need to take a closer look at the Sensor results here. Please open a ticket at [email protected] with the following attached information.

Please enable "Write result to disk" in the sensor's "Settings" tab. With the next scan it will write one or several result-files into C:\ProgramData\Paessler\PRTG Network Monitor\Logs (Sensors) of your PRTG server (or on the Remote Probe if applicable). All files have the sensor's numeric ID in their filenames. The sensor ID can be found on the sensor's "Overview" tab. Please send us those result-files.

Thanks in advance.

Kind regards,
Birk Guttmann, Tech Support Team

Created on Nov 6, 2018 1:41:31 PM by  Birk Guttmann [Paessler Support]



Thanks. I have enabled writing to disk and the logs have been created, so I will create a new case and attach the logs to that.

I could only do this for 1 sensor, as I had already deleted the other one in order to re-create it, which is when I got the error mentioned in my original topic, so I hope these other logs are of use.

Created on Nov 7, 2018 11:37:04 AM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.