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SNTP error 85



I am evaluating PRTG right now and have an error that seems to be intermittent. Almost every Cisco router/switch will show the following error from time to time. The alert goes away for a while, but returns. I have verified that each device is getting time from our NTP master and each device is set to the correct time. Is there a known bug with the SNTP sensor, or is there a way to globally adjust the settings of a sensor or to globally disable a sensor? Thanks.


alert snmp sntp

Created on Jun 12, 2014 2:25:46 PM

1 Reply




When an SNTP-Sensor throws the PE085 error, then the sensor did not receive a response in the expected format. If the sensor only does this every now and then, so switches between UP and this error, then it would be interesting to see what happens, with a Wireshark-Recording where a successful scan and a failed scan (sensor in error) are recorded. We have a case with the same error recently, where analyzing the data showed, that the "Peer Clock Stratum" was set to "unspecified or invalid" and the "Reference ID" seems to contain either random symbols or maybe a dns name with "the wrong codepage". This probably causes an error while reading the response packet and that is why PRTG displays this error message. Wireshark also displays "unidentified reference source" as it couldn't parse this block. Maybe this happens here as well.

best regards

Created on Jun 16, 2014 1:32:47 PM by  Torsten Lindner [Paessler Support]

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