generic-unspecified Bearer End

[John Marrett]

I am experiencing intermittent issues with session disconnects on a private
APN on the AT&T network. When experiencing the issue we see "bearer call
end reason (1): 'generic-unspecified'" in the ModemManager logs.

I'm running Modem Manager version 1.8.0 with custom control scripts, we
aren't presently using Network Manager. The modem is a Sierra Wireless
MC7354 running SWI9X15C_05.05.58.00 r27038 carmd-fwbuild1 2015/03/04
21:30:23. Rebooting the modem (cold boot) and restarting the embedded
system driving it (including a modem reboot) do not affect the behaviour.
This specific site observed the problem for three days last week, it then
worked properly for two days and resumed the disconnection after 72 hours
of clean behaviour. There are three other devices located at this same
site. Two of them have shown no issues in the past two weeks, one followed
a similar pattern to this one for the first period of session disconnects
but did not resume with the other unit.

AT&T indicates that the modem itself is disconnecting from the network and
that the disconnect is not tower or network initiated. I have received
control plane packet captures that I intend to compare with these logs to
confirm the behaviour details this weekend, but wanted to see if anyone on
the list could offer any guidance.

I would like to run in debug mode but I can't restart the ModemManager
process remotely without an unacceptable risk of connection loss. If
there's a way to enable debug mode on the running Modem Manager process I
could get much more detailed info from the site.

Thanks very much for your help, I'm ready to provide any information
required, logs follow,

-JohnF

Feb 22 15:20:18 device ModemManager[932]: <info>  bearer call end reason
(1): 'generic-unspecified'
Feb 22 15:20:18 device ModemManager[932]: <info>  bearer verbose call end
reason (3,1028): [cm] (null)
Feb 22 15:20:18 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connected ->
registered)
Feb 22 15:20:19 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (registered ->
connecting)
Feb 22 15:20:20 device ModemManager[932]: <info>  QMI IPv4 Settings:
Feb 22 15:20:20 device ModemManager[932]: <info>      Address: 10.x.x.225/30
Feb 22 15:20:20 device ModemManager[932]: <info>      Gateway: 10.x.x.226
Feb 22 15:20:20 device ModemManager[932]: <info>      DNS #1: 8.8.8.8
Feb 22 15:20:20 device ModemManager[932]: <info>      DNS #2: 8.8.4.4
Feb 22 15:20:20 device ModemManager[932]: <info>         MTU: 1430
Feb 22 15:20:20 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connecting ->
connected)
Feb 22 15:35:58 device ModemManager[932]: <info>  bearer call end reason
(1): 'generic-unspecified'
Feb 22 15:35:58 device ModemManager[932]: <info>  bearer verbose call end
reason (3,1028): [cm] (null)
Feb 22 15:35:58 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connected ->
registered)
Feb 22 15:35:59 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (registered ->
connecting)
Feb 22 15:35:59 device ModemManager[932]: <info>  QMI IPv4 Settings:
Feb 22 15:35:59 device ModemManager[932]: <info>      Address: 10.x.x.35/29
Feb 22 15:35:59 device ModemManager[932]: <info>      Gateway: 10.x.x.36
Feb 22 15:35:59 device ModemManager[932]: <info>      DNS #1: 8.8.8.8
Feb 22 15:35:59 device ModemManager[932]: <info>      DNS #2: 8.8.4.4
Feb 22 15:35:59 device ModemManager[932]: <info>         MTU: 1430
Feb 22 15:35:59 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connecting ->
connected)
Feb 22 15:51:08 device ModemManager[932]: <info>  bearer call end reason
(1): 'generic-unspecified'
Feb 22 15:51:08 device ModemManager[932]: <info>  bearer verbose call end
reason (3,1028): [cm] (null)
Feb 22 15:51:08 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connected ->
registered)
Feb 22 15:51:09 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (registered ->
connecting)
Feb 22 15:51:09 device ModemManager[932]: <info>  QMI IPv4 Settings:
Feb 22 15:51:09 device ModemManager[932]: <info>      Address: 10.x.x.85/30
Feb 22 15:51:09 device ModemManager[932]: <info>      Gateway: 10.x.x.86
Feb 22 15:51:09 device ModemManager[932]: <info>      DNS #1: 8.8.8.8
Feb 22 15:51:09 device ModemManager[932]: <info>      DNS #2: 8.8.4.4
Feb 22 15:51:09 device ModemManager[932]: <info>         MTU: 1430
Feb 22 15:51:09 device ModemManager[932]: <info>  Modem
/org/freedesktop/ModemManager1/Modem/0: state changed (connecting ->
connected)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/modemmanager-devel/attachments/20190222/d73c7507/attachment.html>