MC7304 disconnects after 24h

Hi,

My MC7304 modem disconnects after more or less 24h. It is not the usual DHCP issue, because the link disconnects within a lease time of dhclient. If you set up a connection again, the problems are solved again for more or less 24h.

In pastebin I attached the logs of libqmi and ModemManager. It contains the RAW QMI messages as well the translated versions. I try to figure out why the modem after 24h disconnects

This is a link to the log: pastebin.com/iTDGqxnj

Till line 50: Everything goes well, ModemManager polls the signal strength. This goes on for 24h. I left one in as an example
From line 50: From this message onwards, the connection gets killed.

This behavior happens on two different mobile operators.

These are the versions I am using:
Modem: MC7304
Kernel: 3.16
ModemManager: 1.4.18
Libqmi: 1.17.900

What is going wrong in the QMI messages an how can I fix it?

check AT+CPIN? when it disconnected

The issue seem cause by carrier.
I don’t know which carrier you are used.
but there are many carrier will let UE disconnect and the UE need re-connect.

It is make sure the resource is alive.