Value 0 of an item when device is OFF

[daru]

I'm in need of assistance with configuring a Zabbix item for monitoring the total pages printed on a printer. Specifically, I aim to retrieve the last value of printed pages with a time shift from 12 am (midnight) today up until the current moment (when viewing the dashboard).

Here's the current expression I'm using:

last(//pages.printed.total) - first(//pages.printed.total, 1d:now/d+1d)

This expression correctly provides the pages printed today, but I also want to ensure that when the printer is OFF, the item value returns 0 instead of the following error:

Cannot evaluate function: not enough data at "first(//pages.printed.total,1d:now/d+1d))".

Any suggestions on how to modify the expression to achieve this behavior would be greatly appreciated.

Thank you!

[solution]

Try preprocessing

https://www.zabbix.com/documentation/current/en/manual/config/items/preprocessing

Example for "Check for not supported value":



Or try others and check the "Custom fail" option:




One of the options will help you.
Wellington