[Starlingx-discuss] Instance can't be accessed when using centrilized router?

I deploy stx-openstack on top StarlingX 3.0. When I used distributed router, I can access my instance from floating IP, but when using centralized router, it can't. I try to find logs on neutron-server logs but there is no log (where all log saved?). I use flat network as provider network. Is it a common behavior if it only can use distributed or there is something I should add on my config?