I'm posting my question in the forum rather than the one for the R7800 router I'm using, because it should be the same matter on any of the routers with a USB port. and running DD-WRT. I’m sorry if my question is addressed elsewhere, but I’ve searched for 2 days without finding a solution that works. I’m also sorry that I’m long winded in this post, but I wanted to explain why I need USB tethering for this setup, instead of using WiFi alternatives that I already have working.
I am trying to get a Netgear 815s, AT&T mobile hotspot using USB tethering to work as the WAN connection for a Netgear Nighthawk X4S AC2600/R7800 model router. I’ve flashed the R7800 router with the V3.0-r34330M kongat (01/02/2018) version of KONG’s DD-WRT firmware. I’ve used DD-WRT for many years extending WiFi in my house and those of friends, so I easily got these two working where the 815s hotspot is the main router and the R7800 is the client extender. My problem is that I for the build I’m trying to set up, I really need a wired USB connection where the DD-WRT on the R7800 will be the main NAT router and using the 815s hotspot as its WAN connection for Internet access. I found a thread at the link below where one user said it worked for them, but their config example isn’t working for me. I don’t know if it’s because I’m using a different version of DD-WRT, if AT&T has changed their firmware in the 815s hotspot, or if I’m missing some other needed config setting the person didn’t include in his example.
After my initial failed attempt with the USB tethering, I’ve now got it working as I have my home routers, where I have a range extending router set to use the 5GHz band as a WPS Station. This lets both routers to provide AP at full speed on 2.4GHz. For setups without Apple devices that don’t need 5GHZ WiFi otherwise, using the 5GHz band for the connection between routers works really well. Before I got routers with 5GHz, a similar setup using only 2.5GHz dramatically reduced my WiFi performance.
For many reasons in addition to the USB 3.0 speed, the setup I’m configuring now for a friend will work much better if I can get the USB tether to work. He now uses lots of these AT&T hotspots for his business where he has people around the country that don’t work in the main office. Often they are in locations that have lots of other WiFi networks very close that cause WiFi band conflicts. This is a annoyance with one person with a laptop, which can be overcome by connecting the hotspot to to the laptop using USB, which automatically configures everything itself with a Windows laptop. He’s now got a new project where there will be 3 or 4 people with laptops, printers, and devices working in small LAN, so he’s adding the the R7800 router with DD-WRT to the mix. The R7800 will have an eSATA solid state drive and function as a file server, web server, and printer server, in addition to basic NAT router and WiFi functions
Using a wired USB connection between the hotspot and the DD-WRT router will make them much easier for the remote users to set up. He needs to be able to ship them to people that can simple plug them in and work, without those people having to know how to do any DD-WRT config of WiFi or anything else. They shouldn’t need to know more than how to plug in Ethernet and power cables, and connect the laptops to the router’s WiFi SSID if needed. The 815s hotspot has a config option to have it turn off its WiFi automatically whenever it’s USB tethered, which will help the R7800 router’s WiFi work better with less chance of band conflicts. They will be connecting laptops, tablets, phones, and printers to the R7800 using both wired Ethernet and WiFi. Ideally, the DD-WRT router will only require that they plug in its power cord and the USB cable to one of the 815s hotspots they already have and normally use with their laptops.
If I can get the 815s with USB as the WAN, the R7800 with DD-WRT provides better security and functionality for things like DDNS, firewall, and VPN server and client tunneling to other sites. If I must use WiFi to connect the hotspot to the R7800 DD-WRT router, then the small 815s hotspot will be the main NAT router for the LAN, and its stock firmware doesn’t provide nearly the capabilities of DD-WRT on the R7800. The reasons for needing USB tethering versus connecting as I’ve got them so far using 5GHz, are the same as when I learned years ago for my home that I should set my ISP’s device in bridged mode so that my DD-WRT devices could play well together.
I’d like to give a shout out to all of the developers who have worked on DD-WRT to applaud all of their work. I began working on enterprise network administration more than 30 years ago. It almost seems like science fiction when I think how this router running DD-WRT does everything and more than what a small room full of equipment that was required in 1999. Even more amazing to me than the reduction in size, power requirements, and cost of the hardware needed, is that DD-WRT makes it possible to configure all of this functionality using a simple web interface. Even though I’ve spent 2 days trying unsuccessfully to get the USB tethering to work, I had it doing 95% of what my friend needed in less than hour after the postman delivered the hardware, including finding the latest DD-WRT firmware and flashing the router.
If anyone has one of these Netgear 815s mobile hotspots with AT&T service working with USB tethering as the WAN connection for a DD-WRT router, I’d deeply appreciate any insight and assistance you can provide to me. I’d offer to name my first child after anyone who can help, but I’m old, single, and don’t plan to have kids, so it will have to be my next dog instead.
Greg
Thanks for the info! I have the same setup (hotspot and router models) but I can't get this to work for the life of me.
I'm on the ddwrt build from here:
http://www.desipro.de/ddwrt/K3-AC-IPQ806X/
The three modules aren't showing. I see usbnet.ko, but neither cdc_ether.ko or rndis_host.ko. I'm pretty sure I've successfully added the startup script (copy-pasted into the box, and hit 'save startup', and it shows in the startup box), but I suspect without these two modules, I won't be able to operate the router this way. Any insight you could offer would be much appreciated!