12.11. Bounce Queue

Options used:

• lpd_bounce FLAG produces a single file for forwarding

• bq_format=format of filtered files

When the destination of a spool queue is another spool queue the job is simply forwarded without any modifications. However, sometimes it is essential that the job be modified before forwarding, as when the remote spool queue is actually a printer, and jobs need to be converted to the format acceptable by the remote printer or banner pages added.

The lpd_bounce flag marks a spool queue as a bounce queue. Lpd will perform all of the usually job processing steps, such as banner generation, filtering files, etc, but saves the output to a file. This file is then sent to the destination print queue for further processing.

    # Simple example of a bounce queue
    bounce:lp=bounce@bouncehost
    bounce:server
        :lp=lp@remote
        :lpd_bounce
        :sd=/var/spool/lpd/%P
        :filter=/usr/local/bin/lpf
        # uncomment ab if you want banner
        #:ab

Some comments:

1. The lpd_bounce option marks the job as a bounce queue, and the lpd server will process the job through the appropriate filter programs.

2. The printcap has filter specifications for different job formats. These are the programs that will be used by LPRng to process the job.

3. The bq_format specifies the job format for the output file sent to the remote spool queue. If not specified, it defaults to l (literal or binary).

4. The ab (always print a banner) flag will force a banner to be added to the job. The banner generation is done as discussed in Banner Printing.