CUPS son siglas de Common Unix Printing System, y no sólo es para impresoras remotas:
Cita:
Iniciado por http://www.cups.org/ CUPS provides a portable printing layer for UNIX®-based operating systems. It is developed and maintained by Easy Software Products to promote a standard printing solution and is the standard printing system in MacOS® X and most Linux® distributions.
CUPS uses the Internet Printing Protocol ("IPP") as the basis for managing print jobs and queues and adds network printer browsing and PostScript Printer Description ("PPD") based printing options to support real-world printing.
No sé cuál es tu problema, pero seguro que te da una ayuda mirar los logs de CUPS. Se encuentran en el directorio
/var/log/cups, y son dos ficheros:
access_log y
error_log
¿Dicen algo interesante?