Re: GSM dongle fails to connect

[Aleksander Morgado <aleksander lanedo com>]

Hey Radu,

Which modem is this? If it's a Huawei modem, your issue may be known
(wrong tty used for data).


>       * on the new system, Mobile Broadband is disabled by default; if I
>         enable it, I can see an "orange UMTS" entry in the
>         active/available connections list. It shows a signal strength
>         icon, but the list entry is grayed out.

That's the information about the current network where the modem is
registered, and the user is not supposed to click on it. You're not the
only one confused about this:
https://bugzilla.gnome.org/show_bug.cgi?id=658230

>       * The connection that I used for making the debug capture is
>         manually added, using "Edit connections..." -> Add, and then
>         selecting my provider/plan from the list. Even though the phone
>         number that's configured is "*99#", I can see Modem Manager is
>         actually dialing "*99***2#". From what I've read, "***2" is a
>         profile selection and maybe that's the problem. Any idea where
>         that "***2" is coming from?

Your modem has probably different PDP contexts configured (APNs, IP
type...), ModemManager will try to activate the PDP context
corresponding to the settings you passed, the one with CID=2 in your
case. Nothing to worry about here, unless you're really passing the
wrong APN in the settings.

> 
> I'm an experienced linux user with fairly decent programming knowledge,
> so I can assist at least with tests and debugging data if anyone is
> willing to help me. However, I don't know anything about the
> NetworkManager architecture and GSM modems in general.

I would try to grab both ModemManager and NetworkManager debug logs. See
the "Debugging NetworkManager 0.8 and 0.9 3G connections" section at
https://live.gnome.org/NetworkManager/Debugging.

Cheers,

-- 
Aleksander