Orbi AX 6000 and AT&T fiber gateway issue

Bypassing ATT Router BGW-210 RGW ( residential gateway),
Dumb switch method by spoofing MAC on the Router.

(Currently I am not using this method but thanking all others who contributed to this knowledge bellow)

This procedure works well when you don't need to power reset your router frequently. Since NG needed many firmware updates in the past and will need few more in the future and sometimes requres hard or factory reset, this method will be annoying for some people. That is why I am still using the Pass Through Mode, with NAT server disabled with no problem on my BGW-210 RGW. Also my son gets his X-box Ethernet directly from this modem and he didn't have to deal with Orbi WiFi router problems especially  like problems after March 9 firmware ordeal. 

I heard that earlier ATT modems have problems with Orbi routers and will benefit from this method because they have no Pass through mode.
With my old non-NG router this procedure was perfect and only was repeated once in many months  when sync was lost due to a power failure. Get a power back up if you don't want this to happen.

Q. Why completely bypass the ATT gateway instead of using the pass through method?
A. Because some experts believe that some activities, including NAT and the Firewall can't be completely disabled on the ATT gateway and it will slow down the internet because your NG router unnecessarily will do the same things all over again and maybe can do the job better and faster if it is doing byitself. ( No double NATing).
Q. Why do you need the dumb switch instead of plugging the router right into the ONT?
A. Because even though ATT does not track the RGs, they just require one to authenticate. Your fiber service address is tied to ONT SNID.
ONT must always re authenticate with the ATT RGW when the Ethernet plug is disconnected. The dumb switch just keeps the link up while you connect your router (with the spoofed mac).

Steps

1) Define your gateway's mac on the WAN port of whatever router you want to use (asus, netgear, etc). WAN connectivity should be via dhcp.
To find out the MAC Address type 192.168.1.254 to connect to ATT RGW from your browser.

clone this MAC Address to your new Netgear router.
type http://192.168.0.1 or http://192.168.1.1
The default username is admin and the default password is password.

2) I'm using a simple dumb switch (Netgear GS105) to handle ONT/RGW/Router connectivity.

2a) With everything from a fully off state, allow the ONT to register (~2 min) the fiber connection first. During this time there's nothing but fiber and power plugged into the ONT.

2b) Connect ONT's Ethernet port to one port of the dumb switch.

2c) Connect the WAN port of the RGW to another port on the dumb switch.

2d) Connect power to the RGW

3) Wait 1-2 minutes for both lights to become solid green on the RGW.

4) You can now power down and disconnect the RGW from the dumb switch.

5) Connect your router's WAN port to the dumb switch. Turn the router on.

6) Within a minute or less it should acquire the same IP, gateway and DNS as the gateway had.

7) Enjoy

"ONT reregistration will only be necessary if power to the ONT or dumb switch is disrupted. In that case, repeat steps 2b-5.