'port forced close' after failed ppp

[Aleksander Morgado]

On Tue, Mar 7, 2017 at 3:46 PM, Colin Helliwell
<colin.helliwell at ln-systems.com> wrote:
>> > > Mar 7 10:05:25 wg2 daemon.debug pppd[944]: sent [IPCP ConfReq id=0x1 <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.484324] [src/mm-port-serial.c:1294] mm_port_serial_open(): (ttyMux0) device open count is 2 (open)
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.484745] [src/mm-port-serial-at.c:459] debug_log(): (ttyMux0): --> 'AT+CGACT?'
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.513270] [src/mm-port-serial-at.c:459] debug_log(): (ttyMux0): <-- '+CGACT: 1,0OK'
>> >
>> > *HERE*
>> >
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.514773] [src/mm-base-bearer.c:172] load_connection_status_ready(): connection status loaded: disconnected
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.515912] [src/mm-port.c:94] mm_port_set_connected(): (ttyMux1): port now disconnected
>> > > Mar 7 10:05:25 wg2 daemon.info ModemManager[896]: [1488881125.516973] [src/mm-iface-modem.c:1431] __iface_modem_update_state_internal(): Modem /org/freedesktop/ModemManager1/Modem/0: state changed (connected -> registered)
>>
>> That is the standard connectivity check done by MM using AT+CGACT?.
>> Looks like the modem is reporting PDP context 1 (the one you used for
>> connecting) is disconnected (state 0)?
>>
>
> Yes, I see what you mean. Now, [my] confusion is: the PDP is (I believe) being activated on ttyMux1 - the virtual port which is set as the PPP port. But the connectivity check is being done on ttyMux0 - the primary port.
> So, is MM expecting to be able to check the connectivity of the PPP port via the primary? That would make sense, I guess - but I'm wondering (to myself) how the modem's multiplexer deals with this i.e. whether it sees a distinction between which port the AT+CGACT? is done on.

I see your concern; but if the modem is a single one and it just has
multiple AT ports, I would assume that there isn't a list of PDP
contexts per TTY, that wouldn't make much sense, would it?. Another
thing would be able to activate different PDP contexts on different
TTYs, but that is unrelated, the actual list and state of PDP contexts
should be the same for all TTYs. At least that is what I would expect!

> BTW - is the connectivity check new since 1.6?
>

It is only in git master, hasn't been released yet:
37bd61421245de87d2c04852109d2a1b14d338cb

> I'm now back at a previous working state, by exposing only one port to MM. With this I can get ppp connection, albeit with connectivity check and signal quality failing because the port is in use.

Yep.

> So I need to figure out whether I can get MM to be able to monitor the connection on ttyMux1, using ttyMux0.
> Surely ought to be possible - otherwise what's the point in having the query command if it won't fetch you the answer for the other port?! Might be something I need to dig into at the modem Mux's end of things. If I'm understanding things right, that is. e.g. Is there a difference between a 'PDP [#1] context activation' and the 'ATD*99***1##' ?

The 1 in ATD*99***1## refers to PDP context #1 (i.e. starts data
connection in PDP context 1). Not sure if that's what you mean.

-- 
Aleksander
https://aleksander.es