Setup port

Webserver Ports

openHAB has a built-in webserver, which listens on port 8080 for HTTP and 8443 for HTTPS requests. In general, it is advised to use HTTPS communication over HTTP.

The default ports 8080 and 8443 can be changed by setting the environment variables OPENHAB_HTTP_PORT resp. OPENHAB_HTTPS_PORT. In an apt installation, you would best do this in the file /etc/default/openhab2

sudo systemctl daemon-reload
sudo systemctl restart openhab2

Verify if OH2 is listening to the new TCP (http) port with:

sudo netstat -atn | grep 8081

forum source

 open hab source