Specifications

2-48
Guide to Printers and Printing
Remote printing overview
Remote printing allows different computers to share printers. To use remote printing
facilities, the computers must be connected via the Transmission Control Protocol/Internet
Protocol (TCP/IP) and must support the required TCP/IP applications, such as the lpd
daemon.
A remote print request is queued in the same manner as a local print request:
• A front–end print command such as qprt, lpr, or enq initiates the request to the
appropriate queue on the local system.
• The qdaemon on the local system processes the request as it would any locally queued
job, with one exception. The qdaemon passes the request to the rembak backend
program rather than the piobe backend.
• The rembak program transmits the print job to a remote server via the TCP/IP network.
• On the remote server the lpd daemon monitors port 515 for remote print requests.
• When the lpd receives a remote print request, it places the job in the appropriate local
queue.
• The print request is then processed by the qdaemon on the print server.
• The qdaemon passes the request to the piobe backend on the print server.
• The piobe backend formats the data stream for printing on the specified printer.
The following sections discuss how to configure, use and manage a remote printing
environment:
• rembak program on page 2-48
• lpd daemon on page 2-49
rembak program
The local queue set up to serve remote print requests must be configured to use rembak,
the remote print backend command. When you set up the queue, the system prompts for a
backend program path name. The entry at this prompt tells the qdaemon command which
backend program to use to process print requests. To set up a queue to handle remote print
requests, enter /usr/lpd/rembak.
The rembak command also processes status requests, job cancel requests, and requests
to kill a remote queuing system. Status requests such as qchk –A or lpstat query the status
of local print queues and devices by analyzing the qconfig file and the local print spooling
subsystem status files.
In a remote print environment, the qchk –A and lpstat commands use the rembak program
to request queue status information from the print servers. The output of a queue status
command shows two entries for each remote queue. The first entry is the status of the local
queue to which remote jobs are sent. The second entry shows the status of the queue on
the remote print server where the jobs are printed. In the following example, the queue
name rq was used for both the queue on the local system and the queue on the remote
print server:
Queue Dev Status Job Files User PP % Blks Cp
––––– ––– –––––– ––– ––––––––––––––– –––––––––– ––– –– –––– ––
Iago Iago RUNNING 284 mileaf ann@arctur 15 13 1 1
Pro asc READY
bsh bshde READY
ps ps READY
rq rqd READY
rq ps1 RUNNING 297 .deskprint/dsktop sarah@alde 60 22 1 1
QUEUED 298 .deskprint/howtol sarah@alde 60 1 2