Bug#969531: avahi-daemon: retrieving printer info blocks printing until shutdown

[Brian Potkin]

On Fri 04 Sep 2020 at 15:23:32 +0200, Michael Hatzold wrote:

> OKI printer B432, conected via USB, no network cable attached.

The B432 is an IPP device; it very likely understands the IPP-over-USB
protocol.

When connected to USB the ipp-usb service is started and ipp-usb takes
control of the only available USB interface.
> 
>* What led up to the situation?
> Want to print
> 
>* What exactly did you do (or not do) that was effective (or
>  ineffective)?
> select document, start print dialog, select my printer (config was done via
> CUPS);

Your manually configured iprinter is not being allowed to access the
USB interface. This is not a bug. Please see sections 14, 15 and 16 at

  https://wiki.debian.org/CUPSDriverlessPrinting
  
> Now the printer appears a second time in the list with a different entry. If I
> select this new entry, I am asked for CUPS PW twice, then it (a deamon,
> whatever) starts retriving printer info which *never* completes.

That was a GTK bug at the time. 

>* What was the outcome of this action?
> Either way, selecting my own entry or the new one made by the daemon, the
> printer does nothing (I waited up to 45 minutes... until I shutdown my system.
> Them during shutdown, there is a pause during which the document gets printed.

Pass.
 
>* What outcome did you expect instead?
> I want the printer to print after I sent the job.
> 
> 
> *** End of the template - remove these template lines ***
> 
> There is a workaround:
> 
> In the original /etc/avahi/avahi-daemon.conf file, there is an entry "#allow-
> interfaces=eth0".
> Changing and uncommenting it to "allow-interfaces=eth9" solves the problem
> (printer not conected via ethXYZ, though). 

"allow-interfaces=eth9" effectively prevents avahi-daemon from working
on all interfaces, including the loopback interface. ipp-usb is exposed
on the loopback interface by default.

avahi-daemon is now completely crippled; it may as well be purged from
the system.

>Therefor I assume this hides a bug
> or an improper default configuration.

There isn't any bug in avahi-daemon.

Regards,

Brian.

Bug#969531: avahi-daemon: retrieving printer info blocks printing until shutdown

[Michael Hatzold]

Package: avahi-daemon
Version: 0.8-3
Severity: important

Dear Maintainer,

*** Reporter, please consider answering these questions, where appropriate ***

OKI printer B432, conected via USB, no network cable attached.

   * What led up to the situation?
Want to print

   * What exactly did you do (or not do) that was effective (or
 ineffective)?
select document, start print dialog, select my printer (config was done via
CUPS);

Now the printer appears a second time in the list with a different entry. If I
select this new entry, I am asked for CUPS PW twice, then it (a deamon,
whatever) starts retriving printer info which *never* completes.


   * What was the outcome of this action?
Either way, selecting my own entry or the new one made by the daemon, the
printer does nothing (I waited up to 45 minutes... until I shutdown my system.
Them during shutdown, there is a pause during which the document gets printed.

   * What outcome did you expect instead?
I want the printer to print after I sent the job.


*** End of the template - remove these template lines ***

There is a workaround:

In the original /etc/avahi/avahi-daemon.conf file, there is an entry "#allow-
interfaces=eth0".
Changing and uncommenting it to "allow-interfaces=eth9" solves the problem
(printer not conected via ethXYZ, though). Therefor I assume this hides a bug
or an improper default configuration.



-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.8.5-towo.3-siduction-amd64 (SMP w/2 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages avahi-daemon depends on:
ii  adduser  3.118
ii  bind9-host [host]1:9.16.6-2
ii  dbus 1.12.20-1
ii  init-system-helpers  1.58
ii  libavahi-common3 0.8-3
ii  libavahi-core7   0.8-3
ii  libc62.31-3
ii  libcap2  1:2.43-1
ii  libdaemon0   0.14-7+b1
ii  libdbus-1-3  1.12.20-1
ii  libexpat12.2.9-1
ii  lsb-base 11.1.0

Versions of packages avahi-daemon recommends:
ii  libnss-mdns  0.14.1-1

Versions of packages avahi-daemon suggests:
pn  avahi-autoipd  

-- Configuration Files:
/etc/avahi/avahi-daemon.conf changed:
[server]
use-ipv4=yes
use-ipv6=yes
allow-interfaces=eth9
ratelimit-interval-usec=100
ratelimit-burst=1000
[wide-area]
enable-wide-area=yes
[publish]
publish-hinfo=no
publish-workstation=no
[reflector]
[rlimits]


-- no debconf information