Allied Telesis AT-S25 - Manual (Page 160)

Section II: Local and Telnet Mangement
160
Changing the Aging Time
The switch uses the aging time to delete inactive dynamic MAC
addresses from the MAC Menu. When the switch detects that no packets
have been sent to or received from a particular MAC address in the table
after the period specified by the aging time, the switch deletes the
address. This prevents the table from becoming full of addresses of
nodes that are no longer active.
To adjust the aging time, perform the following procedure:
1. From the Main Menu, type 5 to select System Config Menu.
2. From the System Config Menu, type 5 to select MAC address aging time.
The following prompt is displayed:
Enter MAC address aging time -> [8 to 512]
3. Enter a new value in seconds. The range of the MAC Address aging
time is 8 to 512 seconds. The default value is 300 seconds (5 minutes).
Changes to the settings take effect immediately on the switch.