How to use OKI 810dn on Ubunts
Installation
Select "AppSocket/HP JetDirect"
IP:10.4.7.41
Port:9100
Driver:oki, C5800
Other setting
"Printer Options" tab, "Color Mode" -> Color
"Printer Options" tab, "Page size" -> A4
"Printer Options" tab, "Media source" -> Tray1, and rotate A4 papers to 'tate' if it was A4 'yoko'