original file https://gist.github.com/sieste/77c004a263f1da38688e119c7b4758b8

Install brother printer DCP-J4120DW


install driver with pacman brother-dcpj4120dw
open localhost:631 in webbrowser
Administration -> Add Printer
to authenticate, use username 'root' and your root password
Internet Printing Protocol (IPP)
put "ipp://192.168.1.8:631/ipp/print" into Connection field (using the correct IP)
fill in "Name" field
Make:"Brother", Model:"Brother DCP-J4120DW CUPS (en)"
click "Add Printer"
set default options and click "Set Default Options"
Maintainance -> Print test page