Chapter 7
| Spanning Tree Algorithm
Configuring Interface Settings for STA
– 210 –
not cause the spanning tree to initiate reconfiguration when the interface
changes state, and also overcomes other STA-related timeout problems.
However, remember that Edge Port should only be enabled for ports
connected to an end-node device. (Default: Auto)
■
Enabled
– Manually configures a port as an Edge Port.
■
Disabled
– Disables the Edge Port setting.
■
Auto
– The port will be automatically configured as an edge port if the
edge delay time expires without receiving any RSTP or MSTP BPDUs. Note
that edge delay time (802.1D-2004 17.20.4) equals the protocol migration
time if a port's link type is point-to-point (which is 3 seconds as defined in
IEEE 802.3D-2004 17.20.4); otherwise it equals the spanning tree’s
maximum age for configuration messages (see maximum age under
“Configuring Global Settings for STA” on page 201
An interface cannot function as an edge port under the following conditions:
■
If spanning tree mode is set to STP (
), edge-port mode cannot
automatically transition to operational edge-port state using the automatic
setting.
■
If loopback detection is enabled (
) 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 212
When edge port is set as auto, the operational state is determined
automatically by the Bridge Detection State Machine described in 802.1D-2004,
where the edge port state may change dynamically based on environment
changes (e.g., receiving a BPDU or not within the required interval).
◆
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 guard can only be configured on an interface if the edge port attribute is
not disabled (that is, if edge port is set to enabled or auto).
Содержание GTL-2881
Страница 30: ...Figures 30 Figure 450 Showing RIP Peer Information 669 Figure 451 Resetting RIP Statistics 670 ...
Страница 34: ...Section I Getting Started 34 ...
Страница 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Страница 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Страница 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Страница 229: ...Chapter 8 Congestion Control Automatic Traffic Control 229 Figure 135 Configuring ATC Interface Attributes ...
Страница 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Страница 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Страница 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Страница 670: ...Chapter 18 Unicast Routing Configuring the Routing Information Protocol 670 Figure 451 Resetting RIP Statistics ...
Страница 672: ...Section III Appendices 672 ...
Страница 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Страница 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Страница 696: ...Glossary 696 ...
Страница 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...