H3C Technologies H3C S7500E Series Switches - Manual (Page 114)

9-3
Broadcast mode: If the device receives a frame with the destination address being all ones, or no
entry is available for the destination MAC address, the device broadcasts the frame to all the
interfaces except the receiving interface.
Figure 9-1 Forward frames using the MAC address table
Configuring a MAC Address Table
The MAC address table configuration tasks include:
Configuring MAC Address Table Entries
Disabling MAC Address Learning
Configuring the Aging Timer for Dynamic MAC Address Entries
Configuring the MAC Learning Limit
These configuration tasks are all optional and order independent. You can perform them as needed in
any order.
Configuring MAC Address Table Entries
Usually, a device can populate its MAC address table automatically by learning the source MAC
addresses of received frames.
To improve port security, you can manually add MAC address entries to the MAC address table to bind
ports with MAC addresses, thus fending off MAC address spoofing attacks.
In addition, you can configure blackhole MAC address entries to filter out packets with certain source
or destination MAC addresses.
Follow these steps to add, modify, or remove entries in the MAC address table globally:
To do… Use the command… Remarks
Enter system view system-view —
Add/modify a MAC address entry
mac-address { dynamic | static }
mac -address interface
interface -type interface-number
vlan vlan-id
Required
Use any of the two commands.