Usual problem : printer is added but "Hold for Authentication" message is shown and no page gets printed.
- On nethserver : add the printer in CUPS. Nothing special here, just follow the wizard.
- On OS/X : do NOT add the printer listed in the default section ("Bonjour Shared") in the add printer dialog. Instead, go to the "Windows" tab and look for your printer shared through SMB. You'll need to authenticate yourself (Nethserver / SMB credentials).
Finish the wizard and test the printer.