I have a fresh setup with OpenVSwitch 2.3 (and a second with 2.4). If I add the controller, no switching happens. I found googling around that it is advisable to set the protocols on the bridge controlled by ODL to OpenFlow13. Still nothing happens. If I push a flow with a low priority that has the normal-action switching happens and I can do other flows to supersede this. However isn't the l2-switch app supposed to accept the new packets and then do the switching logic? Do I need to set 'controller' as default action? And no, downgrading OVS is not an option.