Basic concepts

An MFF-enabled device has two types of ports: user port and network port.

An MFF user port is directly connected to a host and processes the following packets differently:

• Allows DHCP packets and multicast packets to pass.

• Delivers ARP packets to the CPU.

• After learning gateways' MAC addresses, a user port allows only the unicast packets with the gateways' MAC addresses as the destination MAC addresses to pass. If no gateways' MAC addresses are learned, a user port discards all received unicast packets.

An MFF network port is connected to any of the following networking devices:

• An access switch.

• A distribution switch.

• A gateway.

• A server.

A network port processes the following packets differently:

• Allows multicast packets and DHCP packets to pass.

• Delivers ARP packets to the CPU.

• Denies broadcast packets other than DHCP and ARP packets.

You need to configure the following ports as network ports:

• Upstream ports connected to a gateway.

• Ports connected to the MFF devices in a cascaded network (a network with multiple MFF devices connected to one another).

• Ports between devices in a ring network.

Link aggregation is supported by network ports in an MFF-enabled VLAN, but it is not supported by user ports in the VLAN. You can add the network ports to link aggregation groups, but cannot add the user ports to link aggregation groups. For more information about link aggregation, see Layer 2—LAN Switching Configuration Guide.

	NOTE: A network port is not always an upstream port. If you enable MFF for a VLAN, each port in the VLAN must be a network or user port.