H3C Technologies H3C S6300 Series Switches - Manual (Page 355)

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gateway's MAC address, the MFF device updates the MAC address upon receiving an ARP packet with
a different source MAC address from the default gateway.
MFF working mechanism
An MFF-enabled device implements Layer 3 communication between hosts by intercepting ARP requests
from the hosts and replies with the MAC address of a gateway. This mechanism helps reduce the number
of broadcast messages.
The MFF device processes ARP packets as follows:
• After receiving an ARP request from a host, the MFF device sends the MAC address of the
corresponding gateway to the host. In this way, hosts in the network have to communicate at Layer
3 through a gateway.
• After receiving an ARP request from a gateway, the MFF device sends the requested host's MAC
address to the gateway if the corresponding entry is available. If the entry is not available, the MFF
device forwards the ARP request.
• The MFF device forwards ARP replies between hosts and gateways.
• If the source MAC addresses of ARP requests from gateways are different from those recorded, the
MFF device updates and broadcasts the IP and MAC addresses of the gateways.
Protocols and standards
RFC 4562, MAC-Forced Forwarding
Configuring MFF
Enabling MFF
In MFF manual mode, enable ARP snooping on the device.
To enable MFF and specify an MFF operating mode:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter VLAN view. vlan vlan-id N/A
3. Enable MFF.
mac-forced-forwarding
default-gateway
gateway-ip
Use either command.
By default, MFF is disabled.
Configuring a network port
Step Command Remarks
1. Enter system view. system-view N/A