Keep in mind that 4g connection has public IP. so cannot open ports and there will be a double nat issue regardless of how optus ditributes IP's over the 4g network
Not like a dymanic or static IP you get when you have a physical connection, like adsl, cable or nbn
I contacted Billion and they sent me an updated firmware for my 8700VAX, which solved the bridging issue. I now have an AC800S working in IP Passthrough mode on my Billion 8700VAX - I must say Billion have great support, very responsive.
Now that it is up and running, I see what you mean regarding IP Addresses. This does dampen things a little, however I will retain the DSL as a 'backup link' and use it to run, incoming services (VPN) and the Fetch box - which requires the DSL, and run everything else out the 4G.
My bandwidth has gone from 4Mbs to just over 30Mbs by routing out to the 4G interface, and I reckon with an antenna I could probably get closer to 80Mbs as I have line of sight from the roof to a full spectrum Optus tower about 800 metres away. I parked under it the other day with the modem and my laptop and was getting around 85 - 90Mbs - was hoping for more, however, better than 4Mbs. All this just get through, at least, the next twelve months while NBN gets its act together.
Thanks for your input too. If I 'discover' anything else along the journey, I'll report back.
I tired giving the router 192.168.2.25# (it was always at 192.168.1.25#), then couldn't find it and since it's my gateway for devices was just causing endless issues. I reset both devices multiple times.
Finally got it to work but instead of manually setting the usb service to Australia Optus I left on Auto. Also router is where I want it to be e.g. 192.168.1.25#
So far so good with 45Mbp/s - 60Mbp/s and Netflix streaming nicely. Only thing is this optus crowd site doesn't load properly after a long load time :S had to post this via mobile data.
This is axactly what I want to do - to keep my RT-AC66U router as 192.168.1.25* as I have dozens of devices running off of it and don't want to have to change the whole network.
Did the AC800S eventually change its IP range to something other than 192.168.1.25* ?
I have an (almost) identical setup (except I am using the AC810S), and even had the same DNS hangups (I used the 188.8.131.52/184.108.40.206 servers to fix that).
In my case though I want use DDNS from the 8900. To do that I figured I needed to use the IP passthrough feature in the 810 to pass the public IP address to the Billion router rather than the 192.168.1.4 from the 810. Unfortunately when passthrough is activated I loose the Internet connection and the 810 is inaccessible, requiring a factory reset from the 810 display. There is a note on the 810 web interface saying that passthrough only works on Windows and not a Mac, but doesn't say why this is the case nor does it mention routers.
Has anyone else tried that and succeeded, if so, how?
I found this link that suggests maybe a solution is use a Dovado Tiny modem between the 810 and the Billion router may work.