Hi, I'm using my own DHCP & NAT with my own router and I just simply want to use the 3864AC V3 as a gateway and not route to avoid a Double Nat issue But it seems super difficult to place this thing into Bridge mode? I just want the darn thing to act as a modem and not a DHCP server? Does anyone no how to achieve this or have I missed something? Optus have provided me with a static IP which is a start but have no resources to provide me with details on how to Bridge the crippleware modem. Surely I can't be denied that option?!
In my opinion the way to go is to use a mesh router. I have an Orbi with a satellite and simple connect to the Optus modem and using the app it is does all the necessary settings for you. Others on this forum use The Google mesh and I now see Kogan have their own as well as a competitive price.
By doing it this way if you have a home phone you can still plug that into the Optus modem.
I am thinking the same path as @newline if you don't need the optus phone, then remove the 3864v3 all together and use your router as the first point.
Another option is to use your router as your first point and plug in the 3864v3's WAN into the lan port of router. This way your main traffic will only have 1 NAT and the 3864v3 will be use just for the Optus phone line.
If you are very keen then get a ATA like the Cisco spa112 and remove the 3864v3 all together.
I assume that your 'router' is a router (only) and not a modem-router. If it's a modem-router, then you don't need to use the Optus device at all.
If it is a router, then your best bet is to buy a cheap (NBN compatible) modem and put it in bridge mode. Connect the router to it. You could also use your router in its access point mode - that may provide all the functionality you want, without the double NAT issue.