There is a "printers" probe that can monitor printers on Windows robots. Is this available for Unix / Linux?
The printers (Printer Monitoring) probe is configured to monitor printers that are mapped to your system. You can create profiles that monitors live printing jobs. The probe allows you to set the threshold values for monitoring job queue length, printer status, and printing job age. Based on the defined thresholds, you can generate alerts and QoS messages.
Documentation on the printers probe: