Allied Telesis AT-S60 - Manual (Page 201)

Chapter 12: STP, RSTP, and MSTP
Section II: Local and Telnet Management 200
topology changes. If the bridge transitions too soon, not all links
may have yet adapted to the change, resulting in network loops.
The range is 4 to 30 seconds. The default is 15 seconds.
4 - Bridge Max Age
The length of time in seconds after which stored bridge protocol
data units (BPDUs) are deleted by the bridge. All bridges in a
bridged LAN use this aging time to test the age of stored
configuration messages called bridge protocol data units
(BPDUs). For example, if you use the default 20, all bridges delete
current configuration messages after 20 seconds. This parameter
can be from 6 to 40 seconds. The default is 20 seconds.
In selecting a value for maximum age, the following must be
observed:
MaxAge must be less then (2 x (HelloTime + 1)).
MaxAge must be less then (2 x (ForwardingDelay - 1)).
Note
The aging time for BPDUs is different from the aging time used by
the MAC address table.
5 - Bridge Identifier
The MAC address of the AT-8401 management card. This is used
as a tie breaker if two bridges have the same bridge priority
number. You cannot change this value.
4. To change STP port settings, go to the next procedure. If you do not
want to change STP port settings, type R until you return to the Main
Menu. Then type S to select Save Configuration Changes.
Configuring STP
Port Parameters
To adjust a port’s STP parameters, perform the following procedure:
1. From the Spanning Tree Menu, type 3 to select STP Configuration.
The STP Menu is shown in Figure 68 on page 199.
2. From the STP Menu, type P to select STP Port Parameters.