[cups.general] Transient media-empty-error not cleared causes class to not respond

[Jan Engelhardt]

Hi,


I have here a setup with
 - a openSUSE 12.1, cups-server 1.4.6 server and
 - Ubuntu 10.04, cups-client-1.4.3, firefox-3.6.23

In the Firefox print dialog, the troublesome printer is shown with a [-] 
icon and identifying status text:

 "Ready to print. ; Printer 'persatz' is out of paper."

Printing on this printer works nevertheless, as paper is actually in the 
tray(s). Both firefox and lpr succeed in outputting documents.
The `lpstat -p` command also shows no sign of paper problems.

However, we have also a class that contains this (and only this one) 
printer, i.e. we are using the class as an alias. Printing to this class 
leaves the job spinning due to the retention of the out-of-paper 
condition. /var/log/cups/page_log tells us:

[Job 32244] STATE: +connecting-to-device
[Job 32244] Connecting to persatz:631
[Job 32244] Connecting to printer...
[Job 32244] STATE: -connecting-to-device
[Job 32244] Connected to printer...
[Job 32244] Connected to 134.76.82.80:631 (IPv4)...
[Job 32244] prtMarkerSuppliesLevel.1.1 = 6300
[Job 32244] prtMarkerSuppliesLevel.1.2 = 43810
[Job 32244] ATTR: marker-levels=63,19
[Job 32244] Getting supported attributes...
[Job 32244] document-format-supported (5 values)
[Job 32244] [0] = "text/plain"
[Job 32244] [1] = "text/plain; charset=US-ASCII"
[Job 32244] [2] = "application/postscript"
[Job 32244] [3] = "application/vnd.hp-PCL"
[Job 32244] [4] = "application/octet-stream"
[Job 32244] STATE: media-empty-error
[Job 32244] Unable to contact printer, queuing on next printer in class...
[Job 32244] Backend returned status 1 (failed)
[Job 32244] Retrying job on another printer.
[Job 32244] End of messages
[Job 32244] printer-state=3(idle)
[Job 32244] printer-state-message="/usr/lib/cups/backend/ipp failed"
[Job 32244] printer-state-reasons=media-empty-error


1. the media-empty-error state is not reflected in lpstat
or the CUPS webinterface. http://xcups2:631/printers/ only says:

	Idle - "Ready to print."

So how would one determine that there is a problem, without
going for firefox print dialogs or page_log?

2. How to clear this state?

Since printing on the persatz queue does succeed, should CUPS not 
recognize that the media-empty-error state is no longer accurate.