I've got a custom Buildroot-based Linux system (running on a Raspberry Pi) that uses systemd for the init system. I've plugged a Quectel LTE EC20 modem into it and created the following file /etc/systemd/network/10-wwan.network
[Match] Name=wwan0 [Network] DHCP=yes
Now, on reboot, the wwan0 interface is automatically brought up and initialised and I can connect to the internet.
However, I want to be able to configure the APN settings of the modem (custom APN, username, password). Reading through the documentation of the systemd network files, I was unable to see any options that would allow these settings to be modified. How can this be done?