"Backend /usr/lib/cups/backend/socket does not exist!"

[sammiam]

Binary package hint: cupsys

I performed the following steps:

1) Booted into single user mode
2) apt-get update
3) apt-get dist-upgrade

Now I now longer have a working CUPS system.

Here's what versions of cups was loaded prior to the upgrade:

ii bluez-cups 3.9-0ubuntu1 Bluetooth printer driver for CUPS
ii cupsys 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - server
ii cupsys-bsd 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - BSD comman
ii cupsys-client 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - client pro
ii cupsys-common 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - common fil
ii cupsys-driver-gutenprint 5.0.0.99.1-0ubuntu1 printer drivers for CUPS
ii libcupsimage2 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - image libs
ii libcupsys2 1.2.8-0ubuntu5 Common UNIX Printing System(tm) - libs
ii libgnomecups1.0-1 0.2.2-5ubuntu1 GNOME library for CUPS interact

Here's what versions of cups I now show:

ii bluez-cups 3.9-0ubuntu3 Bluetooth printer driver for CUPS
ii cupsys 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - server
ii cupsys-bsd 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - BSD comman
ii cupsys-client 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - client pro
ii cupsys-common 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - common fil
ii cupsys-driver-gutenprint 5.0.0.99.1-0ubuntu2 printer drivers for CUPS
ii libcupsimage2 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - image libs
ii libcupsys2 1.2.8-0ubuntu7 Common UNIX Printing System(tm) - libs
ii libgnomecups1.0-1 0.2.2-5ubuntu1 GNOME library for CUPS interaction

When I view my printer via the WEB browser, I see that the printer is in a stopped state. If I try and start it, I see the error message:

"/usr/lib/cups/backend/socket failed" for the printer.

ProblemType: Bug
Architecture: i386
Date: Wed Mar 28 21:37:47 2007
DistroRelease: Ubuntu 7.04
Uname: Linux sammlinux 2.6.20-13-generic #2 SMP Sun Mar 25 00:21:25 UTC 2007 i686 GNU/Linux

[SammIam (iamsamm)]

Here's additional messages from cups error_log:

E [28/Mar/2007:09:04:05 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:15:02:09 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:15:10:55 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:15:19:34 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:16:17:57 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:21:36:44 -0400] Creating missing directory "/var/run/cups/certs"
E [28/Mar/2007:21:44:07 -0400] Resume-Printer: Unauthorized
E [28/Mar/2007:21:44:09 -0400] Resume-Printer: Unauthorized
E [28/Mar/2007:21:44:29 -0400] PID 6974 (/usr/lib/cups/backend/socket) stopped with status 22!
E [28/Mar/2007:21:44:30 -0400] PID 6973 (/usr/lib/cups/filter/foomatic-rip) stopped with status 9!
E [28/Mar/2007:21:49:35 -0400] PID 7203 (/usr/lib/cups/backend/socket) stopped with status 22!
E [28/Mar/2007:21:49:36 -0400] PID 7202 (/usr/lib/cups/filter/foomatic-rip) stopped with status 9!
E [28/Mar/2007:21:54:45 -0400] PID 7350 (/usr/lib/cups/backend/socket) stopped with status 22!
E [28/Mar/2007:21:54:45 -0400] PID 7349 (/usr/lib/cups/filter/foomatic-rip) stopped with status 9!

[SammIam (iamsamm)]

OK, got it working... not sure if this is actually a bug or due to 3rd party vendor's driver...

I have a Samsung ML-2010 Laser printer, and Samsung does provide a driver for their printer. Here's what I did to get this working:

1) via CUPs web admin, I deleted the defined printer.
2) I re-installed the Samsung driver. The driver install will automatically define a printer, but when checking the install, the DEVICE URI was "/dev/null".
3) I noticed that in /usr/lib/cups/backend that there was no file called "socket", however, there was a file in /usr/lib/cups/backend-available called "socket" so I copied it from backend-available over to backend.
4) Using the the CUPs WEB interface, I added a new printer, and was this time able to choose "Apple socket/HP JetDirect" as the interface, and then set "socket://192.168.1.99:9100" as my networked printer.

The printer now works correctly.

[Pascal De Vuyst (pascal-devuyst)]

Thanks for your bug report.

> I noticed that in /usr/lib/cups/backend that there was no file called "socket",
> however, there was a file in /usr/lib/cups/backend-available called "socket"
> so I copied it from backend-available over to backend.

This is an upgrade issue caused by activating all CUPS backends during feisty development, on a clean feisty installation this will not happen anymore.
A better way to activate the missing backends is by using this command:
$ sudo dpkg-reconfigure cupsys

cupsys (1.2.8-0ubuntu8) feisty; urgency=low

  * debian/cupsys.postinst: Clean up the mess which cupsys_1.2.8-0ubuntu3 and
    later caused by activating all the CUPS backends (closes: LP#92042).

 -- Till Kamppeter <email address hidden> Tue, 3 Apr 2007 17:22:06 +0100

cupsys (1.2.8-0ubuntu7) feisty; urgency=low

  * debian/cupsys.postinst: Sync /usr/lib/cups/backend always with the
    debconf settingsm, as otherwise sooner or later the backend directory
    will be empty (closes: LP#92042).

 -- Till Kamppeter <email address hidden> Tue, 14 Mar 2007 16:22:06 +0000