IT/Procedures/Printer Maintenance/Script to prevent printhead drying out

Printer Maintenance Script

About the Issue

A lot of effort has been taken by several people to create a reliable script that prints a test page on all printers every few days.

This should prevent the ink drying out which renders the printer unusable.

So far this feat has not been fully achieved yet :(

How is it setup?

• the script runs every few days as a cron job on the cnx server
• several scripts are under /home/walt/.scripts/PrinterMaintenance
• crontab -e to check which one is active at the moment
• the newer ones are set to create some logs in the same folder (*.log)
• most if not all scripts try to print with lp and check somewhat with lpstat what's around (printers and/or open print jobs)

What is working so far

• there's a script that prints over the access point mode of the printers
  • caveat is that the printer need to be set to ap mode, then back again for normal use
  • so far this was used as a "holiday setup"
• the other scripts try to print over wlan connected to the router
  • this seems to work "mostly" well, at least with the MG3670 printer models
  • depending on the mood of the printer, it will not print anything at all
• send a Telegram notification if any print job ist unfinished

The Issues

• some printers occasionally just don't print anymore and pile up jobs (check lpstat)
  • though this also happens with "legit" reasons, e.g. no paper or printer error
• printers sometimes "dissapear" from the network and are no longer visible through e.g. lpstat -v
• so far no reliable way has been found to resolve the issues automatically

New Approaches and Findings

• configured another printer driver/model in CUPS
  • the default model doesn't support duplex and CMYK printing
  • set address from dnssd (bonjour) to static ip of the printer (to the next volunteer: just change it back if you think this should be done with bonjour ;)
  • see Configure Printer Driver/Model
• printer-maintenance.sh
  • uses a static list of all printers (so no printer is "forgotten" if it dissapears from the network)
  • checks if a printer has any unfinished jobs and deletes them (lprm [PRINTER] -)
  • checks if a printer has the correct driver/model configured, searches for the ColorModel attribute (lpoptions -p [PRINTER_NAME] -l | grep ColorModel | grep CMYK)
    • could probably also be done with e.g. lpoptions -p [PRINTER_NAME] | grep "Canon MX920 series - CUPS+Gutenprint v5.3.3" but would need a different string for every printer model
  • sends a new job
  • waits 1 min, then checks for unfinished jobs again
    • if there are some, this will be logged
    • those printers then need manual maintenance (mechanical issue, wrong driver, or just more paper)
    • sends notification to telegram webhook with output of lpstat
      • could be extended to send to e-mail or some other messenger if needed

Telegram Notifications

In Telegram

• contact "BotFather" to create a new telegram bot send: /newbot

• follow the instructions

• copy the API key

• contact "IDBot" and send: /getid (in a group chat, add IDBot to group and send: /getgroupid@myidbot)

• copy ID (include "-" with group chat IDs")
• paste the API key and ID into the script

Useful Commands

• lp
• lpstat
  • -e
  • -v
• lprm [PRINTER] -
• lpoptions -p [PRINTER_NAME] -l