Multiple Modems (USB Dongle) problem

[John Whitmore]

This is a development list so possibly the wrong place for this question but
please redirect me as necessary.

I've got a problem using two USB LTE Dongle modems of exactly the same
model. They each have a different operators SIM installed. They will both get
added to the linux system (I'm using Arch on a RPi-2) as /dev/cdc-wdm0 and
/dev/cdc-wdm1. BUt they will be added, I imagine, at random.

Managing which is which is the job of UDEV rules so I've added the necessary
rules to create symbolic links to the two modems as /dev/three and
/dev/vodafone.

That all works great my problem is that in the network manager when I add a
connection it only offers me the devices /dev/cdc-wdm0 and /dev/cdc-wdm1. NOT
my new symbolic links.

So given that it's the NetworkManager agian this might be considered the wrong
list. 

Maybe I should explain the system here. This is going into an RPi-2 in a boat
that floats about a lake. So mobile coverage will change between the two
operators. I'm taking this one step at a time and ultimately I'd like the
system to use which ever connection it can. That might be a problem as the
boat needs to have a web site open on the browser. That web page is used to
upload data so the web page is opened and the boat floats about the lake
populating forms in the web page. If the web page is connected via one
connection and the connection changes that might cause a problem. I've not got
there yet. Like I say one step at a time.

This might not even be a problem. I mean maybe the NetworkManager creates a
connection, but then the ModemManager has the intelligence to say that you're
trying to open the "vodafone" connection on the wrong modem and just take care
of it?

John