Remote Printing using the LPR/LPD Protocol at AIX 4.3

Contents

About this document
    Related documentation
How the LPR/LPD protocol works
How to set up an AIX 4.3 print client to an LPD server
How to set up AIX 4.3 as an LPD server
Details of local formatting
Remote printing flags and status filters
Remote printing status
Tracing remote printing
Rembak debug output
LPD debug output
Problem determination
Streaming LPR/LPD
Rembak flags
Canceling remote jobs

About this document

This document describes how to set up remote printing using the LPR/LPD protocol at AIX level 4.3.

Related documentation

AIX and related product documentation is also available:
http://www.rs6000.ibm.com/resource/aix_resource /Pubs/index.html


How the LPR/LPD protocol works

Printing using the LPR/LPD protocol is defined in an RFC 1179. This Request For Comment, although never officially adopted as a standard, is used by most computer, terminal server, printer server, and printer manufactures for doing network printing. Be aware that the standard is incomplete, and does not define any type of error handling, retry capability, or what the client should do when the server is busy. This often times creates problems when printing to network attached printers and print servers using this protocol. When possible, it is recommended when printing to these devices, use the proprietary protocol or socket program provided by the manufacturer. When this is not done, frequently the queue will go down.

The basic syntax of remote printing using LPR/LPD is as follows:

  1. Client sends a print request to server specifying a queue name.
  2. Server acknowledges that the queue exists.
  3. Client sends a packet that contains the temporary filename, and the number of bytes in the file.
  4. Server acknowledges that it has room to accept the job.
  5. Client sends the data file to be printed.
  6. Client sends a packet that contains the control file name and the number of bytes in the control file.
  7. Server acknowledges that it is ready to accept the control file.
  8. Client sends the control file.
  9. Server acknowledges that it has received the file.
  10. Client or Server sends a FIN packet to end transmission.

How to set up an AIX 4.3 print client to an LPD server

AIX 4 allows both local and remote formatting. Local formatting allows a virtual printer to be set up on the local system that will send the data to the remote system with local headers and printer setup information attached. Remote formatting sends the data to the remote server without doing any filtering or formatting of the file and without adding any printer setup commands.

AIX 4 setup with remote (standard) processing

Steps to create a remote queue with no local formatting.

This creates a queue with the rembak backend. It is assumed that the remote system will add headers and trailers, as well as add carriage returns to line feeds. This is the method used by default prior to AIX 4, enter:
	smit mkpq
  1. Select remote Printer Attached to Remote Host
  2. Select Standard processing
  3. Fill in entries on Add a Standard Remote Print Queue screen.
  4. Press Enter to create queue.

AIX 4 setup with local formatting

In this section, you create a local queue that uses an AIX virtual printer to first add printer setup commands and format the data prior to sending the file to the remote hosts. The backend program for this kind of a queue is piorlfb which calls piobe (the virtual printer backend), and then uses rembak to send the formatted file to the remote server.

Reasons why you may consider setting up a local queue that uses an AIX virtual printer follow:

Steps to create a remote queue with local (virtual printer) formatting.

  1. Enter smit mkpq
  2. Select remote    Printer Attached to Remote Host
  3. Select Local filtering before sending to print server
  4. Select Printer Manufacturer
  5. Select Printer Type
  6. FIll in the Add a Remote Print Queue with Local Filtering menu.
  7. Press Enter to create queues.

How to set up an AIX 4.3 LPD print server

There are two steps to setting up an LPD print server on AIX. The first step is to start the lpd daemon on AIX.

  1. Start the lpd remote printer subsystem daemon on the Server System.