1 COP 4343 Unix System Administration Unit 9: printing – lpr – CUPS

2 Printing in Unix Traditional –Berkeley Line Printer Daemon –AT&T Line Printer System Improvements: –typical Linux implementation –LPRng Emerging standard –Internet Printing Protocol: IPP/1.1 –Common Unix Printing System: CUPS

3 Traditional Linux printing PRINTER environment variable command line printing: lpr ex: lpr filename print job maintenance –show print queue: lpq –remove job from queue: lprm

4 lpd daemon configuration –/etc/printcap local or remote printers –print filters queue control per printer –lpc status, start, stop

5 Common Unix Printing System CUPS manages printers in a network –maintains printer definitions –allows printing to network printers maintains lpr commands and /etc/printcap file for backward compatibility

6 CUPS device support lpinfo -v network socket network http network ipp network lpd network smb serial serial:/dev/ttyS2?baud= direct parallel:/dev/lp1 direct usb:/dev/usb/lp0 direct scsi direct hal

7 CUPS setup cups service –yum install cups –enable in run-level: chkconfig cups on –start service: service cups start configuration –/etc/cups/cupsd.conf specify which IP:port to listen on listen on :631 allow access to Location / and /admin allow from –security: allow tcp port 631 in firewall

8 Common Unix Printing System managing CUPS printers –command line interface: lpadmin –old style semi-graphical: printconf –web interface on port printer definitions –ppd files

9 CUPS printer setup printer class –for sets of similar printers –jobs accepted to class will print on one printer in class printer setup –local: device –network: protocol + host + name ex: “lpd://ferret.cs.fiu.edu/venom”

10 CUPS printer setup supported printers –HP, Epson, Okidata, Postscript,... printer options –output resolution, double-sided, banner,...

11 CUPS printing client –PRINTER environment variable –interactive from program lpr or lp lpq lprm lpstat