Configuring Stp; Understanding Spanning-Tree Features - Cisco 2950 - Catalyst Switch Configuration Manual

Configuring STP

This chapter describes how to configure the Spanning Tree Protocol (STP) on port-based VLANs on
your Catalyst 2950 or Catalyst 2955 switch. The switch uses the per-VLAN spanning-tree plus (PVST+)
protocol based on the IEEE 802.1D standard and Cisco proprietary extensions, or it can use the rapid
per-VLAN spanning-tree plus (rapid-PVST+) protocol based on the IEEE 802.1w standard.
For information about the Multiple Spanning Tree Protocol (MSTP) and how to map multiple VLANs
to the same spanning-tree instance, see
For information about other spanning-tree features such as Port Fast, UplinkFast, root guard, and so
forth, see
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:
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Understanding Spanning-Tree Features

These sections describe how basic spanning-tree features work:
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Chapter 16, "Configuring Optional Spanning-Tree Features."
Understanding Spanning-Tree Features, page 14-1
Configuring Spanning-Tree Features, page 14-11
Displaying the Spanning-Tree Status, page 14-24
STP Overview, page 14-2
Spanning-Tree Topology and BPDUs, page 14-3
Bridge ID, Switch Priority, and Extended System ID, page 14-4
Spanning-Tree Interface States, page 14-4
How a Switch or Port Becomes the Root Switch or Root Port, page 14-7
Spanning Tree and Redundant Connectivity, page 14-8
Spanning-Tree Address Management, page 14-8
Accelerated Aging to Retain Connectivity, page 14-8
Spanning-Tree Modes and Protocols, page 14-9
Supported Spanning-Tree Instances, page 14-9
C H A P T E R
Chapter 15, "Configuring MSTP."
Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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14-1