Bug#832637: cups-browsed: Shutdown hangs on A stop job runs for Make remote CUPS printers available locally

[Brian Potkin <claremont102@gmail.com>]

On Sun 21 Aug 2016 at 17:50:41 +0200, Heinrich Schuchardt wrote:

> On 08/21/2016 02:20 PM, Brian Potkin wrote:
> > On Thu 28 Jul 2016 at 02:00:36 +0200, Heinrich Schuchardt wrote:
> > 
> > Thank you for your report, Heinrich.
> >  
> >> every time I shutdown my system I have to wait 90 s for a stop job
> >> showing the message
> > 
> > Is this consistent behaviour?
> 
> Yes, this happened on every shut down until I uninstalled the package
> cups-browsed.

Stopping cups-browsed before powering off should give a clean shutdown.

> >> A stop job runs for Make remote CUPS printers available locally
> > 
> > This should not be happening since 1.9.0-1.
> > 
> >> Shutdown should be as fast as possible.
> >>
> >> The same job could be run in the background at any time.
> >>
> >> Typically systems are shutdown when leaving office and restarting
> >> the system in another network with other printers.
> >>
> >> So looking for remote printers in a shutdown job does not
> >> make much sense. If the job is needed at all, run it when
> >> starting the system.
> > 
> > cups-browsed creates local print queues for remote queues when it starts
> > up. These queues need removing when it closes down. To do this it needs
> > the cups daemon to be running so that it can communicate with it and
> > have it adjust the contents of /etc/cups/printer.conf.
> > 
> > Issue the command
> > 
> >   systemctl stop cups.service cups-browsed.service
> > 
> > It should complete almost immediately. Does it?
> 
> It stops immediately
> 
> > 
> > Look at the output of 'journalctl'. It should show cups-browsed stopping
> > before cups does. This allows communication between the two to continue
> > and is an indication of what should happen at reboot or poweroff.
> 
> Aug 21 17:45:18 LT002 systemd[1]: Stopping Make remote CUPS printers
> available locally...
> Aug 21 17:45:18 LT002 systemd[1]: Stopped Make remote CUPS printers
> available locally.
> Aug 21 17:45:18 LT002 systemd[1]: Stopping CUPS Scheduler...
> Aug 21 17:45:18 LT002 systemd[1]: Stopped CUPS Scheduler.
> Aug 21 17:45:18 LT002 polkitd(authority=local)[2040]: Unregistered
> Authentication Agent for unix-process:5935:652630 (system bus name
> :1.75, object path /org/freedesktop/PolicyKit1/AuthenticationAgent,
> locale de_DE.UTF-8) (disconnected from bus)

We are in agreement. The 'Requires=cups.service' in the cups-browsed
unit file causes cups to wait until cups-browsed has finished what it is
doing before stopping.

However, this was not a full examination of what happens during powering
off. To do that we could really do with seeing what the journal says. In
/etc/systemd/journal.cont the line "Storage=auto" needs uncommenting and
replaced with "Storage=persistent". Reboot.

When next you get the 90s delay the progess of the shutdown is recorded.
Something like

  journalctl --list-boots

and

  journalctl -b -1

should allow you to extract the portion of the log we are interested in
and send it here.

Cheers,

Brian.