H3C S7500 Series Ethernet Switches Operation Manual

Operation Manual – MAC Address Table
H3C S7500 Series Ethernet Switches Chapter 1 MAC Address Table Management
1-5
z If the aging time is too short, the switch may remove valid MAC address entries.
This decreases the forwarding performance of the switch.
Follow these steps to set aging time for MAC address entries:
To do… Use the command… Remarks
Enter system view
system-view
—
Set the aging time of MAC
address entries
mac-address timer
{ aging age | no-aging }
Required
The default aging time is
300 seconds.
This command is used in system view and applies to all ports. Aging applies to only
dynamic MAC addresses that are learnt or configured to age out.
Normally, you are recommended to use the default aging time, namely, 300 seconds.
The no-aging keyword specifies that MAC address entries do not age out.
1.2.4 Setting the Maximum Number of MAC Addresses a Port can Learn
The MAC address learning mechanism enables an Ethernet switch to acquire the MAC
addresses of the network devices on the segment connected to the ports of the switch.
The switch directly forwards the packets destined for these MAC addresses. An
oversized MAC address table may decrease the forwarding performance of the switch.
By setting the maximum number of MAC addresses that can be learnt from individual
ports, you can control the number of the MAC address entries the MAC address table
can dynamically maintains. If you have set the maximum number of MAC addresses
that a port can learn to count, the port stops learning MAC addresses when the number
of MAC addresses learned by the port reaches count.
Follow these steps to set the maximum number of MAC addresses a port can learn:
To do… Use the command… Remarks
Enter system view
system-view
—
Enter Ethernet port view
interface interface-type
interface-number
—
Set the maximum number
of MAC addresses the
port can learn
mac-address
max-mac-count count
Required
By default, the number of
the MAC addresses a port
can learn is not limited.
1.2.5 Disabling MAC Address Learning
To gain better control over network security, you can use the following commands to
disable the current port from learning MAC addresses.