Hello forum

I would like to be able to use KDE Connect to connect* to my LineageOS based mobile. Neither the Linux Mint 18.2 KDE based desktop PC is connected to wifi nor the mobile.
That means I will go to configure static IPv4 for both devices, in order to be on the same network. Physically they are connected with an USB-cable.

Ifconfig does list two interfaces: rmnet0 and dummy0 (not sure which one to take)

Surprisingly I am not able to ping the Linux PC from the Andorid terminal (no answer at all) and the PC cannot ping the mobile (destination host unreachable)
But the mobile can ping it's 127.0.0.1

Question:
What am i doing wrong?

Thank you very much for any feedback

Ralph


PS

* one reason is, that it's more confortable to use the PC keyboard and the larger screen
- AFWall ist disabled on the mobile
- "ADB over network" is activated in LOS (but i am not sure if that is required)