From the perspective of clients, it will appear as if they are connecting to a single server. This destination address, however, will actually be a virtual server on your FortiADC appliance.Once the appliance receives traffic at the virtual server’s IP address, it must apply changes such as decryption and content rewriting (if required) before using the virtual server’s selected session persistence and load balancing methods to distribute the packets to your pool of servers.

You do not specify an IP address for a layer 2 load balance virtual server. Instead of routing data for a specific destination, this type of server routes data from the specified network interface and port. The L2 Load Balance virtual server only routes client requests arriving at the specified interface and port.