ECS4510 Series Web Management Guide-R03

Chapter 7 | Spanning Tree Algorithm
Configuring Interface Settings for STA
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An interface cannot function as an edge port under the following conditions:
■
If spanning tree mode is set to STP (page 201), edge-port mode cannot
automatically transition to operational edge-port state using the automatic
setting.
■
If loopback detection is enabled (page 199) and a loopback BPDU is
detected, the interface cannot function as an edge port until the loopback
state is released.
■
If an interface is in forwarding state and its role changes, the interface
cannot continue to function as an edge port even if the edge delay time
has expired.
■
If the port does not receive any BPDUs after the edge delay timer expires,
its role changes to designated port and it immediately enters forwarding
state (see “Displaying Interface Settings for STA” on page 211).
◆ BPDU Guard – This feature protects edge ports from receiving BPDUs. It
prevents loops by shutting down an edge port when a BPDU is received instead
of putting it into the spanning tree discarding state. In a valid configuration,
configured edge ports should not receive BPDUs. If an edge port receives a
BPDU an invalid configuration exists, such as a connection to an unauthorized
device. The BPDU guard feature provides a secure response to invalid
configurations because an administrator must manually enable the port.
(Default: Disabled)
◆ BPDU Filter – BPDU filtering allows you to avoid transmitting BPDUs on
configured edge ports that are connected to end nodes. By default, STA sends
BPDUs to all ports regardless of whether administrative edge is enabled on a
port. BDPU filtering is configured on a per-port basis. (Default: Disabled)
◆ Migration – If at any time the switch detects STP BPDUs, including
Configuration or Topology Change Notification BPDUs, it will automatically set
the selected interface to forced STP-compatible mode. However, you can also
use the Protocol Migration button to manually re-check the appropriate BPDU
format (RSTP or STP-compatible) to send on the selected interfaces. (Default:
Disabled)
Web Interface
To configure interface settings for STA:
1. Click Spanning Tree, STA.
2. Select Configure Interface from the Step list.
3. Select Configure from the Action list.
4. Modify any of the required attributes.
5. Click Apply.