Siwsslog does not start without internet

[DG7RO]

it is not related to the internet connection. I know it is down as the router is disconnected from internet cable, but switch inside is working and there is no dhcp error or ethernet disconnection (so having no 169.xxx adress)
Swisslog does here not start as the connection check or DNS resolver does not reply any information.
Would be fine to disable the internet check so the programm can start without DNS or on LAN w.o. ISP.

p.s.: I am working as an IT professional in network architecture and monitoring ;-)