Introduction To Mac Address Table - H3C S5500-SI Series Operation Manual

1
MAC Address Table Management Configuration
When configuring MAC address table management, go to these sections for information you are
interested in:
Configuring MAC Address Table Management
MAC Address Table Management Configuration Example
MAC Information Configuration
MAC Information Configuration Example
Interfaces that MAC address table management involves can only be Layer 2 Ethernet ports.
This manual covers only the management of static, dynamic and blackhole MAC address table
entries (source and destination). For the management of multicast MAC address table entries,
refer to Multicast Routing and Forwarding Configuration in the IP Multicast Volume.

Introduction to MAC Address Table

A device maintains a MAC address table for frame forwarding. Each entry in this table indicates the
MAC address of a connected device, ID of the interface to which this device is connected and ID of the
VLAN to which the interface belongs. When forwarding a frame, the device looks up the MAC address
table according to the destination MAC address of the frame to rapidly determine the egress port, thus
reducing broadcasts.
How a MAC Address Table Entry is Generated
A MAC address table entry can be dynamically learned or manually configured.
Dynamically learn a MAC address table entry
Usually, MAC address tables are automatically generated during the source MAC address learning
process of devices.
The following is how a device learns a MAC address after it receives a frame from a port, Port 1 for
example:
1) Check the source MAC address (MAC-SOURCE for example) of the frame, that is, the MAC
address of the device that sends the frame.
2) Look up the MAC address table for an entry corresponding to the MAC address and do the
following:
If an entry is found for the MAC address, update the entry.
If no entry is found, add an entry for the MAC address to indicate from which port the frame is
received.
1-1