Is it possible to use Syncthing with no internet access? And is it possible to have all changes go through a single server?

Connections will be local by default and only between devices you’ve configured to know about each other, so, yeah. You can absolutely set IP numbers for connections yourself if you want to, but you probably don’t need to. However if by local only you mean “no packet must ever leave my LAN” then you need to disable a bunch of stuff.

2 Likes