Disconnection issues after long periods of inactivity

[José]

This is using the Cinterion PLS8-X using QMI.

On Mon, May 2, 2016 at 6:25 PM, Dan Williams <dcbw at redhat.com> wrote:
> On Mon, 2016-05-02 at 10:43 +0200, José  wrote:
>> Hi,
>>
>> this is an issue I am currently having on a Android system using the
>> manufacturer RIL, and although I have also seen it using linux and
>> modemmanger, is more of a general cellular network question.
>>
>> When being inactive for a long period (~24 hours) seems like the
>> connection goes down. The connectivity seems lost (trying to load a
>> webpage of ping a domain fails) but the modem seems active and
>> connected. In this state, when pinging directly to an IP I get
>> outputs
>> similar to the following:
>>
>> PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
>>
>> From 100.82.203.31: icmp_seq=1 Destination Host Unreachable
>>
>> --- 8.8.8.8 ping statistics ---
>>
>> 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time
>> 0ms
>>
>> Can any of you explain what exactly happens? Thanks
>
> What kind of modem is this, and is it PPP-based?
>
> Dan