Reference Guide

Spanning Tree Protocol (STP)

The spanning tree protocol (STP) is supported on the Z9000 platform.

Protocol Overview

STP is a Layer 2 protocol — specified by IEEE 802.1d — that eliminates loops in a bridged topology by enabling only a

single path through the network.

By eliminating loops, the protocol improves scalability in a large network and allows you to implement redundant paths,

which can be activated after the failure of active paths. Layer 2 loops, which can occur in a network due to poor

network design and without enabling protocols like xSTP, can cause unnecessarily high switch CPU utilization and

memory consumption.

FTOS supports three other variations of spanning tree, as shown in the following table.

Table 49. FTOS Supported Spanning Tree Protocols

Dell Networking Term IEEE Specification

Spanning Tree Protocol (STP) 802.1d

Rapid Spanning Tree Protocol (RSTP) 802.1w

Multiple Spanning Tree Protocol (MSTP) 802.1s

Per-VLAN Spanning Tree Plus (PVST+) Third Party

Configure Spanning Tree

Configuring spanning tree is a two-step process.

• Configuring Interfaces for Layer 2 Mode

• Enabling Spanning Tree Protocol Globally

Related Configuration Tasks

• Adding an Interface to the Spanning Tree Group

• Removing an Interface from the Spanning Tree Group

• Modifying Global Parameters

• Modifying Interface STP Parameters

• Enabling PortFast

• Prevent Network Disruptions with BPDU Guard

• STP Root Guard

• Enabling SNMP Traps for Root Elections and Topology Changes

• Configuring Spanning Trees as Hitless

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