Dual WAN with Netgear 4G failover

General questions
1

Hi, I’m trying to establish if it is possible to use our Netgear 4G router (M1/MR1100) in IP passthrough mode as a failover WAN, using these instructions as a guide (example 2).

As I see it, there are 2 possible issues with this:

  • The external IP address of the 4G modem periodically changes, meaning that defining a static route to a next-hop using an IP address is going to need adjusting whenever the upstream connection is refreshed
  • There is a quirk in the Netgear firmware that they have thus far not fixed where the IP address assigned via dhcp in passthrough is a /32 address, essentially putting the WAN NIC into a subnet of itself. The BSD based products I’ve used in the past have an option (‘supersede subnet-mask’) which instructs the WAN to adopt the IP address issued by the modem but use a subnet mask of your choosing, eg /28. Is there a similar option in Vyos?

Thoughts? Thanks!

2

I had a poor experience with the M1 some time back on EdgeOS that still doesn’t look to be solved. The IP passthrough is implemented in a very hacky manner which didn’t play very well.

I got rid of the device so never was able to test on Vyos, but something to be aware of if you’re seeing issues with connection stability.

More info here.

https://community.ui.com/questions/Flaky-network-behaviour-Nighthawk-M1-IP-passthrough/2105499c-bb81-4afc-bc4a-e03a868e5be7?page=1

3

Hmm, yes I had read that… looks like Netgear might have finally acknowledged the issue by adding an ‘LTE subnet mask’ option to the newer M5, but I doubt they will make the effort to back-port it to the M1/M2 models.

I actually found the M1 to work exceptionally well with *sense routers, once the mask issue was dealt with on the router side.