diff options
Diffstat (limited to 'USAGE')
| -rwxr-xr-x | USAGE | 119 |
1 files changed, 104 insertions, 15 deletions
@@ -185,27 +185,25 @@ detects many file types (text, PDF, most image formats) and together with ImageMagick (for images) and GNU/ESP/AFPL GhostScript 6.51 or newer (for PDF) it converts them to PostScript. The other tools convert only text files. The tool you have installed is auto-detected -by foomatic-rip and used automatically if -necessary. PPR needs this tool only for printing the option -list, and CUPS does not need it at all. PPR and CUPS use internal filters for printing non-PostScript files. +by foomatic-rip and used automatically if necessary. PPR needs this +tool only for printing the option list, and CUPS does not need it at +all. PPR and CUPS use internal filters for printing non-PostScript +files. -If you have a multi-function device from HP, install HPOJ from +If you have a printer or multi-function device from HP, install HPLIP from - http://hpoj.sourceforge.net/ + http://hpinkjet.sourceforge.net/ before starting to set up printer queues with foomatic-filters. This -is needed for printing on USB devices and for scanning and photo -memory card access on all devices. If you use CUPS 1.1.12 or newer -together with the old HPOJ 0.8, you need also the latest "ptal" -backend script from +is needed for printing on certain USB devices and for scanning and +photo memory card access on all devices. It also adds maintenance +functionality for inkjets, reporting of ink or toner levels and +printer status, and also remote readout of the printers front-panel +LCD. CUPS is required as the printing system when HPLIP is used. - http://www.hornclan.com/~mark/cups/ +Note: The "hp" CUPS backend and "beh" (see below) cannot be used +together. -License information and installation instructions for this script you -find in the beginning of the script itself. See also the end of the -"Adding a queue" section in this file to see how to use this script. - -The "ptal" backend script is already included in HPOJ 0.9. Setting up printers @@ -243,3 +241,94 @@ Usage of PPD files (for all spoolers): http://www.linuxprinting.org/ppd-doc.html + + +beh - Backend Error Handler +--------------------------- + +A wrapper for CUPS backends to make error handling configurable + +Usually, if a CUPS backend exits with an error status other than zero +(for example if a printer is not turned on or not reachable on the +network), CUPS disables the print queue and one can only print again +if a system administrator re-enables the queue manually. Even restarting +CUPS (or rebooting) does not re-enable disabled queues. + +For system administrators this can get annoying, for newbie users +who are not aware of this problem it looks like that CUPS is severely +broken. They remove and re-install print queues, getting on the nerves +of distro install support, people, or even switch back to a proprietary +operating system. + +This script makes the handling of such backend errors configurable, so +that the problem can easily be worked around. The new possibilities are: + + - Let queues simply not being disabled. Simple approach, but job gets + lost. + + - Repeat a given number of times. + + - Repeat infinitely often, until the job gets finally through. This + is the standard of LPRng, and it eliminates loss of the job. + + - The interval between two attemts to run the backend can also be + configured. + + - Configuration is done independently for each print queue. So local + printers and network printers can be treated differently. + + +Usage: + +Make sure "beh" is in the CUPS backend directory (usually +/usr/lib/cups/backend/) and world-readable and -executable. Restart +CUPS (usually "killall -HUP cupsd" or "/etc/init.d/cups restart"). If +all is correct "lpinfo -v" should have "beh" in its output. + +Then activate "beh" for your print queue(s) with command(s) like this: + +lpadmin -p <queue name> -E -v beh:/<dd>/<att>/<delay>/<originaluri> + +with + <queue name>: The name of your print queue + <dd>: Don't Disable, if "1", beh always exits with zero + status, so the queue gets never disabled when the + original backend exits with an error. "0" carries + the error status of the last call of the backend + (after <att> retries) on to CUPS, so the queue + usually gets disabled. + <att>: Attempts, number of attempts to recall the backend + in case of an error. "0" means infinite retries. In + this case <dd> gets meaningless. + <delay>: Delay between two attempts to call the beckend, to + be given in seconds and as an integer number. + Meaningless if <att> is one. + <originaluri>: The original URI, which your queue had before. Can + be determined with "lpstat -v". + +All parameters, especially, <dd>, <att>, and <delay> have always to +be specified, even if one of them is meaningless due to the setting of +the others. + +beh works with every backend except the "hp" backend of HPLIP. + +Example URIs: + +beh:/1/3/5/socket://printer:9100 + + On the network printer with host name "printer" it is tried to access + 3 times with 5 second delays between the attempts. If the job still + fails, the queue is not disabled (and the job discarded). + +beh:/0/10/60/socket://printer:9100 + + Retry 10 times in one minute intervals, disable the queue when still + not succeeding. + +beh:/1/0/60/usb://Brother/HL-5040%20series + + On a Brother HL-5040 on the USB try infinitely often until the printer + comes back, in intervals of one minute. This way the job does not get + lost when the printer is turned off and one can intendedly delay + printing by simply switching off the printer. The ideal configuration + for desktop printers and/or home users. |