And that is the problem.
OH REST is only using POST to set a state.
GET is only avaliable with the old Classic-UI, which i don´t want to install only to get GET…
→ https://community.openhab.org/t/solved-use-url-to-manipulate-items-in-oh2/8732/13
As far as I know GET is working fine with HomeMatic, FHEM, ioBroker.
so i have to use POST:
curl -X POST --header "Content-Type: text/plain" --header "Accept: application/json" -d "test" "http://openhabian:8080/rest/items/sv_Camera"
…is working:

Is this all i have to do?!
what can be added here?

At the moment nobody want´s to jump arround infront of my cam ![]()
