USB Tether Cell to ASUS Merlin RT-AC68U in Failover Mode

[colecaz]

I am setting up a Moto G5+ phone running Android Oreo to use with my RT-AC68U in dual WAN failover mode. Running Merlin 380.69_2. I'm planning on having it as backup for the times I lose my primary cable internet service (not often) or if the exterior cable feeding the house gets cut. I count on internet for all sorts of home automation stuff and remote monitoring.

It seems to work fine if I connect to the router USB 3.0 port and manually enable USB Tethering mode in the phone. But if the router USB port loses connectivity with the phone for some reason, USB tethering turns off and will not automatically re-enable. It requires me to manually turn it back on.

I've found several apps that will sense the connection and turn on the tether automatically but they all require root, which I really would like to not do. I've studied various root instructions on the web and none seem to agree how to do it and are incomplete so a nooby gets lost quickly. I don't want to brick the phone experimenting.

Any suggestions? Maybe a different phone? I'd like to stay with the phone concept because I have a Red Pocket plan that gives me 500MB a month for $5 and that would hopefully be enough.

 

[heysoundude]

did you post a similar query on reddit?

 

[colecaz]

No. Is there a solution there? Or did my post get copied?

 

[heysoundude]

I've seen a similar post there on r/wifi IIRC in the past few days.

 

[farfromuman]

I have tried with LG G5 and had the same problem, I am testing a Hotspot/Modem from Alcatel (LINKZONE) with AC86U on 384.8_2, initially it works fine but after some time I get "Network Cable Unplugged" on WAN2 and the device is no longer mounted on the USB port, this also happens when I reboot the router. The only way to fix is to select the USB modem on the WAN setup page and hit apply.

When I plug it in to my Win 10 desktop is stays on-line indefinitely.

 

[colecaz]

heysoundude, I checked reddit and that's not my post. Similar, but not me.

 

[farfromuman]

I think something is wrong with my AC86U, I did the same setup on my AC68U with same firmware and it works perfectly with the Alcatel (LINKZONE) hotspot/modem. The USB connection gets remounted on reboot and gets set as Cold Standby, it would be neat if it was hot but this will do. So far I only tested unplugging the WAN port but it switches over and then back when WAN is reconnected. I use T-Moblie prepaid, 2GB at 4G and unlimited 3G for $10 per month.