Spanning Tree Commands 4

spanning-tree

This command enables the Spanning Tree Algorithm globally for the switch. Use the no form to disable it.

Syntax

[no] spanning-tree

Default Setting

Spanning tree is enabled.

Command Mode

Global Configuration

Command Usage

The Spanning Tree Algorithm (STA) can be used to detect and disable network loops, and to provide backup links between switches, bridges or routers. This allows the switch to interact with other bridging devices (that is, an STA-compliant switch, bridge or router) in your network to ensure that only one route exists between any two stations on the network, and provide backup links which automatically take over when a primary link goes down.

Example

This example shows how to enable the Spanning Tree Algorithm for the switch:

Console(config)#spanning-tree

Console(config)#

spanning-tree mode

This command selects the spanning tree mode for this switch. Use the no form to restore the default.

Syntax

spanning-tree mode {stp rstp mstp} no spanning-tree mode

•stp - Spanning Tree Protocol (IEEE 802.1D)

•rstp - Rapid Spanning Tree Protocol (IEEE 802.1w)

•mstp - Multiple Spanning Tree (IEEE 802.1s)

Default Setting

mstp

Command Mode

Global Configuration

Command Usage

•Spanning Tree Protocol

Uses RSTP for the internal state machine, but sends only 802.1D BPDUs.

-This creates one spanning tree instance for the entire network. If multiple VLANs are implemented on a network, the path between specific VLAN

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