[cups.general] spooler queue stops by themselve

[Johannes Meixner]

Hello,

On May 9 06:32 Jo Hobbit wrote (shortened):
> ... lpd-printing protocol works fine and will not stop the queue,
> when the printer is offline.
> 
> There is a different behavior of the both protocols.
> I use a Lexmark(T644) printer
> 
> I put two jobs in the queue
> 
> IPP
> The Printer is online. Trays are removed (No paper).
> -The Printer goes to status 'Waiting for job to complete...'
> Insert one page in tray
> -"Media tray needs to be filled." First job in processing, Second job pending
> Switch off printer
> -"Media tray needs to be filled." First job in processing, Second job pending
> Switch on printer
> -"Media tray needs to be filled." First job completed, Second job processing
> 
> 
> LPD
> The Printer is online. Trays no paper in trays.
> -No Status change.  First job completed, Second job completed
> 
> 
> With lpd-protocol the printer load the jobs into the memory
> and the jobs are marked as completed.
> If the printer is switched off. The jobs are lost.
> 
> With ipp-protocol I have a better control of the jobs.
> The only case I can lose a job is, when the printer is
> switched off and afterwards switched on.
> When the printer is offline I have the change to move all jobs
> on a second printer and no job is lost.
> Even if the printer is turned on with a job in processing mode,
> I will lose it.
> 
> My intention is not to lose any job.

An interesting info which shows how subtle differences inside
the printer make a difference what happens outside of the printer.

What about the AppSocket protocol which has by default
the "waiteof=true" option, see
http://www.cups.org/documentation.php/network.html

I think regardless which protocol you use, there is always
some special situation where you can lose a job (i.e. whenever
it looks "completed" for the backend but actually it isn't).

As far as I can imagine the only way to be really safe against
loss of jobs is to use "PreserveJobFiles On" in the cupsd.conf
file so that you can re-print any job which does of course
fill up the spool directory (up to 500 "MaxJobs")
or you delete all of them using "cancel -a [queue_name]"
or you set "MaxJobs" explicitely to what you like, see
http://www.cups.org/documentation.php/ref-cupsd-conf.html


Kind Regards
Johannes Meixner
-- 
SUSE LINUX Products GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany
AG Nuernberg, HRB 16746, GF: Markus Rex