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Notification on SNMP channel delta in time



Looking for a way to get alerts when users change printer cartridges. Here's the scenario: I monitor toner levels of HP Color LaserJet printers at remote locations. The SNMP Printer Library in PRTG provides me with channels for toner levels of each color, plus alerts when level go below a certain threshold. Now, my primary interest are not the actual toner levels, (because end users replace cartridges themselves as necessary), but the fact that a toner was replaced (leading to a purchase order for new consumables). How can I get a notification based on changes of values within a library channel, and within a certain time span? I.e. getting notified when the toner level of a cartridge jumps up by +70% within 24 hrs. This indicates that the toner was replaced and new consumables need to be ordered. Can this be achieved with library channels at all or do I have to create a custom SNMP lookup first and then build advanced rules on top of that?

channel delta laserjet notifications snmp-library

Created on Mar 20, 2018 4:33:48 PM

3 Replies



Hello there,

Thanks for your inquiry, we appreciate your contact regarding the matter!

Since there isn't a build in solution, I would recommend the following:
- Switch to the settings of the corresponding Channel (Toner).
- "Enable alerting based on limits" and set a Lower Warning/Error Limit (15/5 is set in the lookup).
- Please create a threshold trigger for the corresponding channel, that sends a notification if the toner is above 99%. This would lead to a one time notification, when the toner is renewed.

For any further questions or issues, we're glad to help.

Kind regards,
Birk Guttmann, Tech Support Team

Created on Mar 22, 2018 1:59:45 PM by  Birk Guttmann [Paessler Support]




Thanks for this. Seems to work as intended!

One follow-up question: What is the purpose of setting "alerting based on limits" for each cartridge channel, in addition to the 99% threshold trigger I set for each color under Notifications? Would the latter not be sufficient?

Best regards, Dan

Created on Mar 23, 2018 1:18:11 PM



Hello Dan,

The "alerting based on limits" for each cartridge channel should switch the Sensor to Warning/Error, if the catridge runs out soon.

Kind regards,
Birk Guttmann, Tech Support Team

Created on Mar 28, 2018 8:52:57 AM by  Birk Guttmann [Paessler Support]

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