A port must be a member of both a VLAN and a Private VLAN to be able to forward packets. By default, all ports are VLAN unaware and members of VLAN 1 and Private VLAN 1."
Once the following two conditions are matched, the packet will then be forwarded from port A to port B, and vice-versa.
1.Port A's VLAN is equal to port B's VLAN (regardless Access or Trunk native)
2.Port A's PVLAN is equal to port B's PVLAN