[Rdo-list] can't access quantum API from network host

Hello, I am re-installing a multi-host grizzly cluster, using quantum/OVS. One thing strange is that quantum commands, like "quantum net-list", fail to run on the network host, returned "403 Forbidden" error message. But using the same admin credential, the quantum commands work from the controller node. It used to work before, with my previous install. Should I be worried about it ? Any suggestions on where to start to debug this? Thanks, Xin