Selectively forwarding flow of packets in a network appliance

A network appliance described herein allows the user to selectively forward the flow of packets received through a network port, to a particular egress port. The network appliance creates virtual ports, which can be assigned to the one or more egress ports. The network appliance assigns the flow of packets to the one or more virtual ports in the network appliance. The network appliance decides a forwarding treatment to be applied to the flow of packets, for forwarding the flow of packets to the egress tool ports, based on the virtual port to which the flow of packets is assigned and based on a detected network characteristic. The forwarding treatment can be a decision to drop the flow of packets, or to send the flow of packets to the egress port assigned to the virtual port.