Recipe 14.10. Troubleshooting

14.10.1 Problem

Printing, especially network printing, is probably the most difficult and troublesome aspect of system administration. What tools are there for diagnosing and fixing problems?

14.10.2 Solution

Your first stop is /var/log/cups/error_log. The default log level in cupsd.conf is LogLevel info. This logs errors and ordinary activity. If LogLevel info does not generate enough detail, the highest levels are debug and debug2.

Trying a different printer driver cures a large number of printing problems.

If test pages won't print, try printing other documents. A test page not printing indicates a problem somewhere, but if you can get your work done, you can probably live without the test page.

For network printing, make sure you have connectivity. Ping both IP addresses and hostnames. Try connecting manually to Samba shares. Try printing from the machine to which the printer is attached.

Run the ppd file for the printer through the PPD checker at http://www.cups.org/testppd.php to test for syntax errors.

If you can't decipher for yourself where the problem is, you can post log output and the steps you've tried in help forums. Here is a listing of the more useful ones:

http://printing.kde.org

Specific to printing in KDE, but still a thorough resource for many aspects of printing with CUPS

http://gimp-print.sourceforge.net/p_Mailing_Lists.php3

Help for Gimp-Print drivers

http://www.linuxprinting.org/forums.cgi

Help forums for HP, Epson, Alps, and many more printers

http://www.cups.org/newsgroups.php

CUPS newsgroups

As always, search the archives before posting your query. There is nothing new under the sun.

14.10.3 See Also

• The Troubleshooting-CUPS-and-Asking-for-Help Howto, by Kurt Pfeifle—a wonderful, comprehensive CUPS troubleshooting guide (http://www.cups.org/cups-help.html)