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Disabling MAC address learning on interfaces
When global MAC address learning is enabled, you can disable MAC address learning on a single
interface.
To disable MAC address learning on an interface:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter interface view.
•
Enter Layer 2 Ethernet interface
view:
interface
interface-type
interface-number
•
Enter Layer 2 aggregate
interface view:
interface bridge-aggregation
interface-number
N/A
3.
Disable MAC address
learning on the interface.
undo mac-address mac-learning
enable
By default, MAC address
learning on the interface is
enabled.
Setting the aging timer for dynamic MAC address
entries
For security and efficient use of table space, the MAC address table uses an aging timer for each
dynamic MAC address entry. If a dynamic MAC address entry is not updated before the aging timer
expires, the device deletes the entry. This aging mechanism ensures that the MAC address table can
promptly update to accommodate latest network topology changes.
A stable network requires a longer aging interval, and an unstable network requires a shorter aging
interval.
An aging interval that is too long might cause the MAC address table to retain outdated entries. As a
result, the MAC address table resources might be exhausted, and the MAC address table might fail
to update its entries to accommodate the latest network changes.
An interval that is too short might result in removal of valid entries, which would cause unnecessary
floods and possibly affect the device performance.
To reduce floods on a stable network, set a long aging timer or disable the timer to prevent dynamic
entries from unnecessarily aging out. Reducing floods improves the network performance. Reducing
flooding also improves the security because it reduces the chances for a data frame to reach
unintended destinations.
To set the aging timer for dynamic MAC address entries:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Set the aging timer for
dynamic MAC address
entries.
mac-address timer
{
aging
seconds
|
no-aging
}
The default setting is 300
seconds.
The
no-aging
keyword disables
the aging timer.