The appliances have one management interface (Admin) and two data plane interfaces (Port1, Port2). If all three interfaces are used, it is recommended to connect them to separate virtual switches (vSwitches) in the ESXi host.
Although configuring the necessary vSwitches does not have to be done before installing the appliance, the installation process will be simpler if it is.
See Configure vSwitches for the Virtual Appliance for instructions on how to create and configure vSwitches that can be used by the Virtual Appliance's data plane ports.