Multiple Modems (USB Dongle) problem

[Dan Williams]

On Wed, 2015-10-21 at 10:12 -0500, Dan Williams wrote:
> On Mon, 2015-10-19 at 09:40 +0200, Aleksander Morgado wrote:
> > Hey John,
> > 
> > On Sat, Oct 17, 2015 at 3:16 PM, John Whitmore <arigead at gmail.com> wrote:
> > > This is a development list so possibly the wrong place for this question but
> > > please redirect me as necessary.
> > >
> > 
> > No, this is the correct place to ask :)
> > 
> > > 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.
> > >
> > 
> > Have you tried to rename the interfaces, as systemd does with the WWAN
> > net interfaces and the "predictable network interface names" setup?
> > You should need to do that before the MM udev rules are used.
> > 
> > > 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?
> > 
> > So, the thing here is that NetworkManager should allow binding a given
> > set of mobile broadband settings to a given specific device (based on
> > 'Equipment ID') or SIM (based on ICCID or even MCCMNC); e..g as it can
> > be done with binding settings to a network interface based on the MAC.
> > If that is done, NM would be intelligent enough to enable the correct
> > settings in each modem.
> > 
> > Dan, what's the status of this in NetworkManager? Was any change done recently?
> 
> Um, I wrote it on a plane last week and this week, but not upstream yet:
> 
> http://cgit.freedesktop.org/NetworkManager/NetworkManager/log/?h=dcbw/wwan-connection-filters

I renamed the branch after creating the review bug, it's now:

http://cgit.freedesktop.org/NetworkManager/NetworkManager/log/?h=dcbw/bgo756916-wwan-connection-filters

Dan