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Notificaton on SNMP Printer Sensor Message



We have a printer needing a PCU replaced. I was curious as to why the need to replace a PCU wouldn't have thrown some type of an alert in PRTG. No notification was sent because the printer didn't have a sensor that would pick up that issue...obviously! Usually I just do an auto-discovery of sensors, but I decided to manually add the SNMP Printer Sensor to the printer having issues. All channels are showing up/green in that sensor; however, instead of the sensor showing a "Ready" message, it shows "Replace PCU" message. So...my question is, how can I create a notification based on that message? It's not tripping any alerts currently. Looking through the Notification Triggers for that sensor, it doesn't look like I have the ability to create a notification based on message.

message notification printer snmp

Created on Jan 22, 2019 11:27:27 PM

1 Reply



Hello there,

Assuming that you use the SNMP Printer Sensor, it polls the printer's status message from OID and it returns only text. From what I can tell there is no standardized subset of messages that is returned by this OID, most likely each vendor can make it return whatever they want under certain cirumstances.

It is true that notifications cannot be triggered by a sensor's message alone. The only sensor that can be configured to act on a particular string and change its state would be the SNMP Custom String Sensor. You could use this sensor to query the aforementioned OID and configure i tot switch to error state when this particular string is found.

In my opinion this has one huge flaw: You do not really know what kind of other status messages the printer might return that would be interesting as well to trigger alarms. If the vendor could provide you with all possible status messages, then you could create a sensor that "knows" them all and acts on each returned status message as you like it. The weapon of choice would be the SNMP Custom String Lookup Sensor then in this scenario.

Kind regards,


Created on Jan 23, 2019 11:43:07 AM by  Erhard Mikulik [Paessler Support]

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