Problems with Z-wave after update to 2.3.0

Check like @kvolden suggested via karaf if the serial transport is active:

196 │ Active   │  80 │ 3.12.0.OH              │ nrjavaserial

Also make sure you are using the correct serial port:

dmesg | grep tty

If both does not help clear tmp and cache and restart openHAB (serial transport needs to be installed again):