Cisco Catalyst 3750 - Default Optional Spanning-Tree Configuration; Optional Spanning-Tree Configuration Guidelines

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Catalyst 3750 Metro Switch Software Configuration Guide
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Chapter 16 Configuring Optional Spanning-Tree Features
Configuring Optional Spanning-Tree Features
When the switch is operating in MST mode, BPDUs are not sent on nonboundary ports only if the
interface is blocked by loop guard in all MST instances. On a boundary port, loop guard blocks the
interface in all MST instances.
Configuring Optional Spanning-Tree Features
These sections describe how to configure optional spanning-tree features:
• Default Optional Spanning-Tree Configuration, page 16-9
• Optional Spanning-Tree Configuration Guidelines, page 16-9
• Enabling Port Fast, page 16-10 (optional)
• Enabling BPDU Guard, page 16-11 (optional)
• Enabling BPDU Filtering, page 16-12 (optional)
• Enabling UplinkFast for Use with Redundant Links, page 16-13 (optional)
• Enabling BackboneFast, page 16-14 (optional)
• Enabling Root Guard, page 16-14 (optional)
• Enabling Loop Guard, page 16-15 (optional)
Default Optional Spanning-Tree Configuration
Table 16-1 shows the default optional spanning-tree configuration.
Optional Spanning-Tree Configuration Guidelines
The UplinkFast and BackboneFast features are not supported with the rapid PVST+ or the MSTP.
Table 16-1 Default Optional Spanning-Tree Configuration
Feature Default Setting
Port Fast, BPDU filtering, BPDU guard Globally disabled (unless they are individually configured
per interface).
UplinkFast Globally disabled.
BackboneFast Globally disabled.
Root guard Disabled on all interfaces.
Loop guard Disabled on all interfaces.