Hi  @Marley2010 

Break down this into two parts:

WAN setup and Link Backup.

It is not the same thing. So, don't mix them before you know how things work.

WAN setup, as long as you can keep it working, then this part is finished. Move on the to the Link Backup.

Set up the USB modem WAN interface as the failover line. Then save it. It should be good if you don't see any errors.

DHCP server on your USB modem is no longer a problem for us. You might wanna contact the USB modem support regarding this. I would recommend you keep them in default state if it works. Don't change any parameters if you don't know what that is before you break the thing from the working state.

Hi @Marley2010 

Thanks for posting in our business forum.

Marley2010 wrote

  @Clive_A thanks, but what do you mean by dhcp isn't a problem? Do you mean the omada router will handle dhcp on behalf of the usb modem? The config screen shows that both ways seem to connect to wan fine, but still not clear what the optimal setup is

You don't have to do anything with it. LAN is default and if you need to change, be sure you know what you are doing.

Whether it is a USB modem router or a USB modem, you should always proceed before you know what's correct and good. Trial and error. Know the basics before you try something else.

USB modem, you need to ask if you can change the modem settings.

USB modem router, you should contact the technical support of your modem router. By default, it is DHCP and you don't have to change it. Changing it would not hurt anything but if you network is down, something must be misconfigured.