Could not connect to the internet with my Eero 6+ when directly connect to my Arris NBN modem. I’m on the iiNet PPOE Hugh speed. I tried a few hours of variation of settings, PPOE, etc but nothing. The Eero just wouldn’t connect to the internet when plugged in directly to the Arris. But it worked when I connected it to my existing router  

In the end I decided to just plug into the LAN port of my old TP link router and now I have a 2-NAT system with primary and secondary wifi. It’s definitely not optimal, but I do get the mesh coverage and high speeds that I wanted throughout my home (and I can stick the old router in a box in the corner and still connect to it in case I want to look at any of the advanced diagnostics or change DNS settings etc.)

if anyone else has found a way to connect directly, I would be keen to know! Perhaps this is something iiNet will work to figure out…?