merlin 386.12.2

TL;DR What does '227 Entering Passive Mode (192,168,2,1,224,194).' mean? I have a new Bell HH4000 (Giga Hub) that I've connected to my Asus RT-AC3100 which is in mesh with another one. I have two USB drives plugged into the AC3100 which I want to serve up via the AC3100's FTP server. I had this...