3Com 4500 PWR 26-Port Configuration Manual page 190

If the amount of secure MAC address entries has not yet reach the maximum number, the port will
learn new MAC addresses and save them as secure MAC addresses.
If the amount of secure MAC address entries reaches the maximum number, the port will not be
able to learn new MAC addresses and the port mode will be changed from autoLearn to secure.
The manually configured secure MAC addresses are written to the configuration file; they will not get
lost no matter whether the port is up or down. As long as the configuration file is saved, the secure MAC
addresses can be restored after the switch restarts.
Configuring a secure MAC address entry manually
Before configuring a secure MAC address entry for a port manually, ensure that:
Port security is enabled.
The maximum number of secure MAC addresses allowed on the port is set.
The security mode of the port is set to autoLearn.
Follow these steps to configure a secure MAC address entry manually:
To do...
Enter system view
In system
view
Add a secure
MAC address
entry
In Ethernet
port view
Configuring an aging time for learned secure MAC address entries
By default, learned secure MAC addresses will never age out; they are deleted only when the port
security feature is disabled or the security mode is not autoLearn any more. However, the learned
secure MAC addresses are not deleted when the security mode turns to the secure mode from
autoLearn.
You can configure an aging time for secure MAC address entries. When the timer of an entry expires,
the entry is removed from the secure MAC address table.
Follow these steps to configure an aging time for learned secure MAC address entries:
To do...
Enter system view
Enable port security
Configure the aging time for
learned secure MAC address
entries
Use the command...
system-view
mac-address security mac-address
interface interface-type interface-number vlan
vlan-id
interface interface-type interface-number
mac-address security mac-address vlan
vlan-id
Use the command...
system-view
port-security enable
port-security timer autolearn
age
15-13
Remarks
—
Either is
required.
By default, no
secure MAC
address entry is
configured.
Remarks
—
—
Required
Aging of MAC address entries
is disabled by default.