WAN Failover and Mobile Tethering

[bbunge]

Over the years I have read that the Asus WAN Failover does not work very well especially when the primary WAN connection comes back up. This weekend Brightspeed suffered a major failure somewhere in its system. I got a report on my mobile from my electrical system monitor that it had lost connection about 1230 Saturday. I was was away at the time and I figured the ISP would have the problem fixed by the time I got home. Wrong! The FIOS was dead. Calling the ISP I learned that the estimated repair time was 1700 Monday. Great. A weekend without internet. I enabled mobile hotspot on my iPhone 14 running iOS 26 beta and tethered it to the AX86U Pro. Voila! The router detected the phone and I had internet even though it was at a poor LTE rate. That was Saturday night. The FIOS connection came back on sometime early Monday morning and the AX86U Pro switched back to the WAN port connection and put the tethered iPhone connection into standby.
Connection failures like this have not happened here since we got the FIOS. But, when It happens again I will be ready... Thanks Asus!

 

[jzchen]

A tree knocked down my (at the time) Coax cable service. I got no internet. Don't know why it didn't work but at least Giggle Fiber came out the next morning and replaced the line. Didn't charge me either even though it was our tree branch!

 

[remsta]

How did you do this? I’ve connected my 15 and I get nothing

 

[bbunge]

How did you do this? I’ve connected my 15 and I get nothing

You need to have Personal Hotspot enabled on the iPhone. May be an added cost on your phone plan.

 

[remsta]

You need to have Personal Hotspot enabled on the iPhone. May be an added cost on your phone plan.

I understand that, it was enabled. I just tested it again, if there are less than 3 bars of service (10mbs or below in a speed test), it simply wont work.

 

[Jeje2]

As we had a 36h break in fibre optic cable recently, I now activated the USB-cable optional WAN setting on my RT-BE86U with my Android phone. Tested by disconnecting the WAN -ethernet cable and worked just fine. Connection returned to primary WAN as reconnected the cable.
Now I know what to do, next time this happens - left even an suitable USB cable ready in the router...

 

[bbunge]

I understand that, it was enabled. I just tested it again, if there are less than 3 bars of service (10mbs or below in a speed test), it simply wont work.

I had a very weak LTS signal. The bandwidth via the iPhone USB tethering was about as slow as my old DSL service. But it worked and enabled emails and basic web surfing but no streaming videos.

 

[jzchen]

How did you do this? I’ve connected my 15 and I get nothing

Unfortunately have to agree with @bbunge it is not plug-and-play with iPhones/iOS.

IF you ever see the pop-up whether to allow access on the iPhone I would definitely allow. Primarily though I believe you need to turn on USB tethering on the iPhone.

Android seems a lot more plug-and-play...