how do printers become disabled?

[Scott Dunkley]

Hi,

Is it possible for a printer to become disabled by any other means other than a user marking it as disabled in SAM or on the command line?

Thanks,

Scott.

[Chris Wilshaw · Accepted solution]

Yes.

If the lp subsystem is unable to send a report to a printer device for some reason (physically turned off, corrupt device file etc).

At that point, the lp daemon times out, and disables the printer to prevent it from constantly retrying.

[Mark Grant]

Yes,

If there is a recurring connection problem, it can become disabled. In fact, if there is pretty much any problem with the setup or permissions of the directories and files that "lpstat" is expecting then the printer can become disabled.

[Thierry Poels_1]

hi,

yes, printers are disabled (by lpsched?) if connection to it continiously fails.

regards,
Thierry.

[e. james]

Printers become disabled after a non-zero exit from the interface file in /etc/lp/interface/$PRINTER. The interface file is usually vendor supplied (depending on printer model/type etc). The scheduler hands off the print job to the interface file which then takes care of all the details of contacting the printer, sending the job, and disconnecting.

Some interface files are robust enough to continue to attempt to contact the printer for long periods of time. This allows for a printer to be down for routine maintanance (supplies exhausted, user rebooted for $REASON_OF_THE_DAY, etc), come back up, and still print without getting disabled. The timeout for this varies with whatever is configured in the interface file. Other interface files try a few times, fail, and exit with a non-zero status, which causes the scheduler to mark the printer disabled. The scheduler figures that the interface file told it there was a problem large enough that required intervention. After the problem is resolved then the sysadmin would enable to printer again.

This is only why it may be getting disabled. Depending on the printer vendor you may want to talk to them about increasing the timeout, or talk to the users and see if they are powering the printer off for long periods of time (like when they go home) and the timeout is not long enough in the interface file. You may also check to see if they are leaving it up but with supply errors for long periods.

Hope this helps you out a bit.

cheers,
e. james

[Keith Bevan_1]

Scott,

The answer to your question is yes !

There are a multitude of reasons that can cause this issue and most of the replies have already covered this.

As a temporary fix you can take some of the pain out of re-enabling the queues (if it is happening often) by setting up a cronjob to re-enabled the queues on a periodic basis :-

Cron Item

0,5,10,15,20,25,30,35,40,45,50,55 * * * * /scriptdir/scriptname 2>&1


scriptname

for lpqname in `lpstat -a | cut -f 1 -d " "`
do
/usr/bin/enable $lpqname
done
exit


Keith

[Thomas Bianco]

Anecdotal: I've seen printers disabled for something as simple as a printer restart.

This is quite a problem, as I need to call in the HPUX support guys whenever someone restarts one of the slower booting printers.