Management Plane Appliance Proxy Hub (MP APH) to host connectivity - TCP:1234 Central Control Plane (CCP) to host (NSX-Proxy) connectivity - TCP: 1235 esxcli network ip connection list | grep 1234 is the correct answer.
https://docs.vmware.com/en/VMware-NSX/4.1/administration/GUID-7F899902-6884-40D0-B0AF-DF713AB05