3Com Switch 4800G 24-Port - Configuring MAC Address Table Management

174 CHAPTER 20: MAC ADDRESS TABLE MANAGEMENT CONFIGURATION
As shown in Figure 46, when forwarding a frame, the switch looks up the MAC
address table. If an entry is available for the destination MAC address, the switch
forwards the frame directly from the hardware. If not, it does the following:
1 Broadcast the frame.
2 After the frame reaches the destination, the destination sends back a response
with its MAC address. (If no response is received, the frame will be dropped.)
3 Upon receipt of the response, the device adds an entry in the MAC address table,
indicating from which port the frames destined for the MAC address should be
sent.
4 Forward subsequent frames destined for the same MAC address directly from the
hardware.
5 Discard the frames which cannot reach the destination MAC address.
Figure 46 Forward frames using the MAC address table
Configuring MAC
Address Table
Management
This section covers these topics:
■ “Configuring MAC Address Entries” on page 174
■ “Configuring MAC Address Aging Timer” on page 175
■ “Configuring the Maximum Number of MAC Addresses an Ethernet Port or a
Port Group Can Learn” on page 175
Configuring MAC
Address Entries
Follow these steps to add, modify, or remove entries in the MAC address table:
Port 1 Port 2
MAC address Port
MAC A 1
MAC B 1
MAC C 2
MAC D 2
MAC A
MAC B
MAC C
MAC D
To do… Use the command… Remarks
Enter system view system-view -
Add/modify a MAC address entry mac-address blackhole mac-address vlan
vlan-id
Required
mac-address { dynamic | static }
mac-address interface interface-type
interface-number vlan vlan-id
Enter Ethernet port view interface interface-type interface-number -
Add/modify MAC address entries
in the specified port view
mac-address { dynamic | static }
mac-address vlan vlan-id
Required