[cups] What is the preferd method to connect cups 1.7.5 to cups 1.3.9

[Johannes Meixner]

Hello,

FYI so that you know the final result:

On Mar 2 11:03 Johannes Meixner wrote (excerpt):
> On Mar 1 10:53 Rick Cochran wrote (excerpt):
>> 
>> Sometimes port 9100 connections from our (non-CUPS LPRng)
>> server get stuck in a FIN-WAIT2 state, causing the queue
>> to get stuck.
...
>>> ... Pförtsch, Franz wrote (excerpt):
>>>> It was working for hours, suddenly the spooljobs get stucked
>>>> in the <local-queue>. The status of the queue was processing
>>>> and the spooljobs showed "Data file sent successfully."
...
> As far as I see when viewing the backend/lpd.c souces
> after the "Data file sent successfully." message
> (in case of the normal "ORDER_CONTROL_DATA",
> i.e. control file first, then data)
> the lpd backend basically does nothing more
> except to close the LPD socket connection
> (via plain "close(fd)" where 'fd' is the LPD socket).
...
> But all this is currently only blind guess from my side.
>
> What is needed is that Franz Pförtsch can find out what
> exactly causes that the backend process does not finish
> after "Data file sent successfully." in his particular
> environment.

My blind guess was wrong.

The actual problem is best described at
http://www.cups.org/str.php?L1933

I can reproduce that when raw printing multiple files
only the first file is sent by the backend but I cannot
reproduce that the job remains active in the queue
where it blocks subsequent jobs from being processed.
In my case a second/third/... job data file is simply
ignored and the queue proceeds with the next print job.

Raw printing multiple files had worked at least in CUPS 1.3.9
but it does no longer work at least from CUPS 1.7.5 up to
CUPS 2.1.3.

I tested CUPS 1.7.5 (on SLES12) and CUPS 2.1.3 (on openSUSE
Leap 42.1) where it does not work and verified that it works
with CUPS 1.3.9 (on SLES11).

I reported the issue to upstream CUPS as
https://www.cups.org/str.php?L4782


Kind Regards
Johannes Meixner
-- 
SUSE LINUX GmbH - GF: Felix Imendoerffer, Jane Smithard,
Graham Norton - HRB 21284 (AG Nuernberg)