Modem creation/startup order

Aleksander Morgado aleksander at
Mon Feb 13 13:40:44 UTC 2017

On Mon, Feb 13, 2017 at 2:05 PM, Colin Helliwell
<colin.helliwell at> wrote:
>> > I’ve got two ports whitelisted for use by MM. What determines which one of
>> > them will be ‘Modem/0’ ?
>> Just the first modem that finishes first probing all ports.
>> > Is there a way to get MM to create/initialise 0 first, then 1 – as opposed
>> > to doing both in *parallel*?
>> Nope, no way, they will be done in parallel. Note, though, that you
>> can "name" modems or refer to them directly using the physical device
>> USB path, which won't change across reboots:
> Thanks. The question arises from needing to have monitoring & URCs etc on one port of my mux driver, and ppp on the other - I need to make sure that ppp doesn't get run on the 'monitoring' port i.e. the one that gets in first with having the URCs enabled.
> This all makes me think I need this 'primary'/'secondary' port stuff - after all that's more or less what the mux is doing too.
> Perhaps I can modify Cinterion's grab_port() to flag the ports as primary/secondary? (They're /dev/ttyMux0, /dev/ttyMux1). Does this sound feasible, or is there more to the dual-portness than that....?

Just setup new Cinterion-specific udev rules to flag ports as primary
or secondary, as done in other plugins; e.g.


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