Cisco Catalyst 3550 Series User Manual

CHAPTER
18-1
Catalyst 3550 Multilayer Switch Software Configuration Guide
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18
Configuring Optional Spanning-Tree Features
This chapter describes how to configure optional spanning-tree features on your Catalyst 3550 switch.
You can configure all of these features when your switch is running the per-VLAN spanning-tree plus
(PVST+). You can configure only the noted features when your switch is running the Multiple Spanning
Tree Protocol (MSTP) or the rapid per-VLAN spanning-tree plus (rapid-PVST+) protocol.
For information on configuring the PVST+ and rapid PVST+, see Chapter 16, “Configuring STP.” For
information about the Multiple Spanning Tree Protocol (MSTP) and how to map multiple VLANs to the
same spanning-tree instance, see Chapter 17, “Configuring MSTP.”
Note For complete syntax and usage information for the commands used in this chapter, refer to the command
reference for this release.
This chapter consists of these sections:
• Understanding Optional Spanning-Tree Features, page 18-1
• Configuring Optional Spanning-Tree Features, page 18-14
• Displaying the Spanning-Tree Status, page 18-22
Understanding Optional Spanning-Tree Features
These sections describe how the optional spanning-tree features work:
• Understanding Port Fast, page 18-2
• Understanding BPDU Guard, page 18-3
• Understanding BPDU Filtering, page 18-3
• Understanding UplinkFast, page 18-4
• Understanding Cross-Stack UplinkFast, page 18-5
• Understanding BackboneFast, page 18-10
• Understanding EtherChannel Guard, page 18-12
• Understanding Root Guard, page 18-12
• Understanding Loop Guard, page 18-13

Cisco Catalyst 3550 Series Specifications

General

Brand	Cisco
Model	Catalyst 3550 Series
Category	Network Router
Language	English