[cups.general] The Famous "Media tray empty!" error - revisited

[Enrique Perez-Terron]

"Steven P. Ulrick" wrote:
> Hello, Again :)
> This is getting kind of old :(  I went to print something, and my
> printing configuration was gone!  After a few feeble attempts at fixing
> it, I rebooted, tried few other things, no luck.  Force installed all
> three CUPS rpm's.  This time it didn't work :(  Now I get this error
> when I attempt to print a test page:
> There was a problem sending CUPS test page
> to 'SamsungML1250LaserPrinter' queue:
>
> lpr: unable to print file: client-error-not-found

May I suggest that you make some special efforts to investigate this:

create a snapshot of /etc/cups, /usr/lib/cups, /usr/share/cups, /var/log/cups, and /var/spool/cups.

You could for instance write a cron job that creates a tarball from these directories every night and keeps the last five such tarballs at all times.

Create one such tarball now, and again when you get the system working again. This is kind of a big hammer, but it should enable us to pinpoint what exactly has changed when the system works and when it does not.

To create a tarball:

su - root -c 'cd /; tar zcf /var/tmp/cups-snapshot-$(date \
+%Y-%m-%d_%H:%M:%S).tar.gz {etc,usr/{lib,share},var/{log,spool}}/cups'

To establish the difference, unpack two tarballs into separate temporary directories, then run diff on the toplevel directories. E.g.,

mkdir /tmp/cups-snap-1 /tmp/cups-snap-2 2>/dev/null;
cd /tmp/cups-snap-1; tar zxf /var/tmp/cups-snapshot-$time_1.tar.gz;
cd /tmp/cups-snap-2; tar zxf /var/tmp/cups-snapshot-$time_2.tar.gz;
cd /tmp; diff -u -r cups-snap-[12] > cups-snaps-diff

Also set the LogLevel in /etc/cups/cupsd.conf to debug:
    (Not tested! Better do this manually:)
  ed /etc/cups/cupsd.conf <<EOF
  /^LogLevel /c
  LogLevel debug
  .
  wq
  EOF

As it is, you could inspect the file(s) /var/log/cups/error_log*
to see if you find any hints.

Regards,
Enrique