I found that a configured wwan interface will stop working after a few days.
I suspect that ISP just want to assign us a new dynamic ip.
To make it working again, I need to disconnect and reconnect wwan0 interface, so, I believe we should add shutdown_required when running the command connect interface wwan0
Steps to reproduce:
- set interface down and up
sudo ip link set dev wwan0 down sudo ip link set dev wwan0 up
- Run ping check (it will failed)
ping 1.1.1.1 interface wwan0
- Re-connect wwan0
sudo mmcli --modem 0 --simple-disconnect sudo mmcli --modem 0 --simple-connect="apn=internet"
- Run ping check (it will work now)
ping 1.1.1.1 interface wwan0
However, I found that cron script is also using command connect interface wwan0.
So just adding shutdown_required will cause cron script to restart too often.