Cisco 2950G 24 Software Configuration Guide - Page 315
Configuring Optional Spanning-Tree Features, Understanding Optional Spanning-Tree Features
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13 C H A P T E R Configuring Optional Spanning-Tree Features This chapter describes how to configure optional spanning-tree features. You can configure all of these features when your switch is running the per-VLAN spanning-tree (PVST). You can only configure the noted features when your switch is running the Multiple Spanning Tree Protocol (MSTP). To use these features with MSTP, you must have the enhanced software image (EI) installed on your switch. For information on configuring the Spanning Tree Protocol (STP), see Chapter 11, "Configuring STP." For information on configuring the Rapid Spanning Tree Protocol (RSTP) and the Multiple Spanning Tree Protocol (MSTP), see Chapter 12, "Configuring RSTP and 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 13-1 • Configuring Optional Spanning-Tree Features, page 13-13 • Displaying the Spanning-Tree Status, page 13-21 Understanding Optional Spanning-Tree Features These sections describe how the optional spanning-tree features work: • Understanding Port Fast, page 13-2 • Understanding BPDU Guard, page 13-3 • Understanding BPDU Filtering, page 13-3 • Understanding UplinkFast, page 13-4 • Understanding Cross-Stack UplinkFast, page 13-5 • Understanding BackboneFast, page 13-10 • Understanding Root Guard, page 13-12 • Understanding Loop Guard, page 13-13 78-14982-01 Catalyst 2950 Desktop Switch Software Configuration Guide 13-1
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