SAP Note 19291 - Setting up printers under UNIX

Symptom:

The most frequent configuration of the print system is: The R/3 system uses access methods 'L' or 'U' to execute print commands at UNIX level.

The UNIX print spooler forwards these commands to a Windows PC or a network where the printers are physically located. The printers must be registered under UNIX as remote printers.

Reason and Prerequisites

Frequent customer inquiries

Solution
The solution varies for different operating systems. One thing that applies to all UNIX systems, however, is that the name of the PC (print server) or the address of the network printer must be maintained in the file /etc/hosts. Furthermore, the print server must permit the UNIX computer to make use of its services.
The following conditions must also apply:
- The following entry must be contained in the file /etc/inted.
printer stream tcp nowait root /usr/librlpdaemon -i -1
- The following entry must be contained in the file /etc /services:
printer 515/tcp spooler
- The Internet daemon must be started

1.) HP:
a.) usr/lib/lpshut
b.) usr/lib/lpadmin -p -v/dev/zero -m -orm -orp
c.) usr/lib/accept name
d.) usr/bin/enable name
e.) usr/lib/lpsched
With a.) the print process is completed,
With b.) a new printer is defined. The name of the printer should appear after the option -p; in this case Name. The option -v allows you to enter the device file which transfers the print data to the computer interface. The -m option allows a printer model to be entered. The printer models available are in the directory "usr/spool/lp/model". A printer driver, which has the name of the printer, is created by lpadmin in the directory "usr/spool/lp/interface". The printer driver is a script.

Note: If the printer created is a local serial printer, you must edit the script manually, in order to set the baud rate, the parity and handshaking (see comment Script).

Using command c.) The files to be printed are copied into this subdirectory by the lp process in accordance with their target printer. Thus, a queue for this printer is managed in this directory.

Using command d.), the lp process calls the printer driver of the printer concerned and transfers the name of the first file to be printed in "request/" as an argument. This file is deleted after printing. The command "usr/bin/disable name" is useful, in that it resets this arrangement so that the files in /request/" are not printed and deleted: The names of these files have the structure "d*". In addition, for each individual one of these files there is a control file "c*" containing administrative information.

The printer driver then creates cover sheets, and copies the files with "cat >> 1" to the device file which causes printout.

With e.) the print process is restarted.

AIX:
The main part of the print system is the queue which is managed by the program /usr/sbin/qdaemon. The queue is used to gather print jobs and to send these to the network according to their priority. The program /usr/lpd/rembak is started by the daemon, which packs the print data into network packages and sends them to the target.

The description of the queues is in the central file /etc/qconfig. For a remote printer queue, the following entry is to be made in this file:
:
host =
sstat_filter =
lstat_filter =
rq =
device = xxxx

xxxx:
backend= rembak

The formatted data are then transferred to the program after the "backend" option. As formatting should take place in the remote system, or has already taken place in R/3, only a dummy is contained here.

Important: Before the entire procedure is started, you should exit the daemon with "enq -G". All pending print jobs are in the directory /var/spool/lpd/qdir. After making any changes, the daemon should be restarted by typing "startsrc -s qdaemon".

A graphic tool "SMIT" is also available under AIX, which can be used to perform the above operations from a series of menus. Nevertheless, it is important to understand the background information described here so that you can respond appropriately to any error messages generated by "SMIT".