On Mon, Aug 23, 2021 at 2:41 PM Bruce A. Johnson <bjohnson@xxxxxxxxxxxxxxxxxxxxx> wrote: > I suspect that ModemManager needs to be changed to inform systemd-networkd. Nothing needs to change in ModemManager. networkd would need to be changed to integrate with ModemManager over D-Bus. The communication would go in 2 directions - networkd telling ModemManager to change states and networkd listening for state changes from ModemManager. FWIW, the NetworkManager code to integrate with ModemManager is in https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/tree/main/src/core/devices/wwan. It uses libmm-glib, but that's really just a convenience wrapper around the D-Bus interfaces. Dan