Cisco WS-C2980G-A Software Guide - Page 157
Configuring Spanning Tree PortFast, BPDU Guard, BPDU Filter, UplinkFast, BackboneFast, and Loop G...
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CH A P T E R 8 Configuring Spanning Tree PortFast, BPDU Guard, BPDU Filter, UplinkFast, BackboneFast, and Loop Guard This chapter describes how to configure the PortFast, BPDU guard, BPDU filter, UplinkFast, BackboneFast, and loop guard spanning tree enhancements on the Catalyst enterprise LAN switches. Note For information on configuring spanning tree, see Chapter 7, "Configuring Spanning Tree." Note For complete syntax and usage information for the commands used in this chapter, refer to the Catalyst 4500 Series, Catalyst 2948G, and Catalyst 2980G Switches Command Reference. This chapter consists of these sections: • Understanding How PortFast Works, page 8-1 • Understanding How PortFast BPDU Guard Works, page 8-2 • Understanding How PortFast BPDU Filtering Works, page 8-2 • Understanding How UplinkFast Works, page 8-3 • Understanding How BackboneFast Works, page 8-4 • Understanding How Loop Guard Works, page 8-6 • Configuring PortFast, page 8-8 • Configuring PortFast BPDU Guard, page 8-11 • Configuring PortFast BPDU Filtering, page 8-13 • Configuring UplinkFast, page 8-15 • Configuring BackboneFast, page 8-17 • Configuring Loop Guard, page 8-18 Understanding How PortFast Works PortFast causes a switch or trunk port to enter the spanning tree forwarding state immediately, bypassing the listening and learning states. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 8-1
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