Printer detection

USB printer

1. Make sure that the printer is connected to your system and powered on.

2. Open a terminal/console and check if the usb kernel modules are loaded: BR $ lsmod | grep usb

3. Unplug the USB printer cable from your computer and enter this command: BR $ tail -f /var/log/messages 

4. Reconnect the USB printer cable, you should see some messages appearing.
5. Press Ctrl-C to stop the logging.

6. Find out if your printer gets detected by CUPS: BR $ lpinfo -v

7. Attach the output of the above commands to the bug report.

Parallel port printer

1. Make sure that the printer is connected to your system and powered on.

2. Open a terminal/console and check if the lp and ppdev kernel modules are loaded: BR $ lsmod | grep lp

3. Check if the kernel detected the parallel port during bootup: BR $ cat /var/log/messages | grep par 

4. Find out if your printer gets detected by CUPS: BR $ lpinfo -v

5. Attach the output of the above commands to the bug report.

Printing bug info

Attach the output of the printingbuginfo script for some useful information about your system related to printing like the version of Ubuntu you use, configured printers and the versions of important printing packages installed. The printingbuginfo script can be found here: https://wiki.ubuntu.com/PrintingBugInfoScript.

CUPS error_log

This is a file where CUPS writes information about what it is doing. Almost all printing problems can be diagnosed from the error log, so it is the first place to look to start solving problems. To be useful, you must change the logging level: BR

1. Edit the file /etc/cups/cupsd.conf, find the line LogLevel and change it to debug, save the file.

2. Restart CUPS: BR $ sudo /etc/init.d/cupsys restart

3. Try to print something.

4. Attach /var/log/cups/error_log to the bug report.

Known bugs

Description of known issues, how to recognise them and stock responses/actions.

Open

Closed

Also see:

• DebuggingProcedures

CategoryBugSquad