initial bearer apn

[Juan A. Rubio]

On Thu, Mar 16, 2023 at 11:43 PM Tom Isaacson <tom.isaacson at teknique.com> wrote:
>
> I raised a bug related to this but haven't had a chance to debug it yet:
> https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/issues/665
>
> When I use QMI I find some SIM cards can connect automatically, they
> don't need me to provide the APN. But ModemManager seems to insist on
> it.
>
>
> On Fri, Mar 17, 2023 at 6:11 AM Peter Naulls <peter at chocky.org> wrote:
> >
> > On 3/16/23 11:53, Juan A. Rubio wrote:
> >
> > > Thanks Peter.
> > >
> > > What mechanism did you use to set the initial bearer? I'm using a
> > > Network Manager connection profile in which I'm setting the APN (e.g.
> > > myapn), not Telstra.internet
> > >
> > > [gsm]
> > > apn=myapn
> > > password=""
> > > username=""
> > >
> > > Do you use mmcli or MM DBus API instead of Network Manager?
> >
> > mmcli where possible.  My of my handling is in OpenWrt's ash; I never
> > quite got to grips with DBus.
> >
> > Here's the section of script where we set the APN; I think logic is clear
> > enough.  I think it likely that there's a better way, but in our testing
> > this is reliable.
> >
> > I'm sure Alex has more commentary here.
> >
> >
> >       config_apn=$(uci get network.wwan.apn 2>/dev/null || true)
> >
> >        initial_bearer_apn=$(mmcli -m $modem_num 2>/dev/null | grep "initial
> > bearer apn")
> >
> >        # Might be blank if not ready yet
> >        if [ -n "${initial_bearer_apn}" ] ; then
> >          curr_apn_value=$(echo ${initial_bearer_apn} | sed 's#.*: ##' || true)
> >
> >          if [ "${config_apn}" == "${curr_apn_value}" ] ; then
> >            message_out "Initial bearer APN correctly set to '${config_apn}'"
> >            apn_check_done=true
> >
> >          else
> >            message_out "Initial bearer APN set to '${curr_apn_value}' vs
> > configured value '${config_apn}' - setting initial bearer"
> >
> >            mmcli -m $modem_num --enable || true
> >            mmcli -m $modem_num
> > --3gpp-set-initial-eps-bearer-settings="apn=${config_apn},ip-type=ipv4v6" || true
> >          fi
> >        fi
> >
>
>
> --
> Tom Isaacson


Thanks.

It still remains a mystery to me where this Telstra.internet default
bearer is coming from.

I'm using a SimCom 7600G by the way.

Do people believe this value is coming from:
- Network Manager,
- Modem Manager,
- SIM card or
- SimCom module?

And perhaps more importantly, is this used at all when the network
call is established by means of a Network Manager connection profile
that contains my own APN?

Juan