Allied Telesis AT-S63 - Manual (Page 431)

AT-S63 Management Software Menus User’s Guide
Section V: Spanning Tree Protocols 431
Table 10 lists the RSTP port costs with Auto-Detect when a port is part
of a port trunk.
3 - Point-to-Point
This parameter defines whether the port is functioning as a point-to-
point port. The possible settings are Yes, No, and Auto Detect.
4 - Edge Port
This parameter defines whether the port is functioning as an edge port.
The possible settings are Yes and No.
5 - Loop Guard
This parameter is used to enable or disable the loop guard feature on a
port. When this feature is enabled, a port that is receiving BPDU
packets is automatically disabled by the switch if there is a cessation of
the BPDU packets without a change to the link state. This protects
against the inadvertent formation of loops in the network topology by
RSTP.
C - Check Migration To RSTP on Selected Ports (MCHECK)
The MCHECK parameter is displayed only when RSTP is enabled.
This parameter resets an RSTP port, allowing it to send RSTP BPDUs.
When an RSTP bridge receives STP BPDUs on an RSTP port, the port
transmits STP BPDUs. The RSTP port continues to transmit STP
BPDUs indefinitely. Type C to reset the MSTP port to transmit RSTP
BPDUs.
9. After making changes, type R until you return to the Main Menu. Then
type S to select Save Configuration Changes.
Enabling or
Disabling BPDU
Guard
BPDU guard is used to prevent edge ports on the switch from being used
by spanning tree devices. It disables edge ports if they receive BPDU
packets. This protects the network topology from unnecessary changes
brought about by the incorporation of new spanning tree devices in the
spanning tree domain. To enable or disable BPDU guard, perform the
following procedure:
1. From the Main Menu, type 3 to select Spanning Tree Configuration.
The Spanning Tree Configuration menu is shown in Figure 151 on
page 416.
Table 10. RSTP Auto-Detect Port Trunk Costs
Port Speed Port Cost
10 Mbps 20,000
100 Mbps 20,000
1000 Mbps 2,000