Redes

Lab 5.5.2: Challenge Spanning Tree Protocol
Topology Diagram

Addressing Table
Device (Hostname) S1 S2 S3 PC1 PC2 PC3 Interface VLAN 99 VLAN 99 VLAN 99 NIC NIC NIC IP Address 172.17.99.11 172.17.99.12 172.17.99.13 172.17.10.21 172.17.20.22 172.17.30.23 Subnet Mask 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0 Default Gateway N/A N/A N/A 172.17.10.12172.17.20.12 172.17.30.12

All contents are Copyright © 1992–2007 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.

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CCNA Exploration LAN Switching and Wireless: STP

Lab 5.5.2: Challenge Spanning Tree Protocol

Port Assignments – Switch 2
Ports Fa0/1 – 0/4 Fa0/5 – 0/10 Fa0/11 – 0/17 Fa0/18 – 0/24 Assignment 802.1q Trunks (Native VLAN 99)VLAN 30 – Guest (Default) VLAN 10 – Faculty/Staff VLAN 20 – Students Network 172.17.99.0 /24 172.17.30.0 /24 172.17.10.0 /24 172.17.20.0 /24

Learning Objectives
Upon completion of this lab, you will be able to: • • • • • • • • • • Cable a network according to the topology diagram Erase the startup configuration and reload the default configuration, setting a switch to the default state Performbasic configuration tasks on a switch Configure VLAN Trunking Protocol (VTP) on all switches Observe and explain the default behavior of Spanning Tree Protocol (STP, 802.1D) Modify the placement of the spanning tree root Observe the response to a change in the spanning tree topology Explain the limitations of 802.1D STP in supporting continuity of service Configure Rapid STP (802.1W) Observe andexplain the improvements offered by Rapid STP

Task 1: Prepare the Network
Step 1: Cable a network that is similar to the one in the topology diagram. You can use any current switch in your lab as long as it has the required interfaces shown in the topology diagram. The output shown in this lab is based on Cisco 2960 switches. Other switch models may produce different output. Set up consoleconnections to all three switches. Step 2: Clear any existing configurations on the switches. Clear NVRAM, delete the vlan.dat file, and reload the switches. Refer to Lab 2.5.1 for the procedure. After the reload is complete, use the show vlan privileged EXEC command to confirm that only default VLANs exist and that all ports are assigned to VLAN 1. Switch#show vlan VLAN Name Status Ports ------------------------------------ --------- ----------------------------1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4 Fa0/5, Fa0/6, Fa0/7, Fa0/8 Fa0/9, Fa0/10, Fa0/11, Fa0/12 Fa0/13, Fa0/14, Fa0/15,Fa0/16 Fa0/17, Fa0/18, Fa0/19,Fa0/20 Fa0/21, Fa0/22, Fa0/23,Fa0/24

All contents are Copyright © 1992–2007 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.

Page 2 of 20CCNA Exploration LAN Switching and Wireless: STP

Lab 5.5.2: Challenge Spanning Tree Protocol

Gig1/1, Gig1/2 1002 1003 1004 1005 fddi-default token-ring-default fddinet-default trnet-default active active active active

Step 3: Disable all ports by using the shutdown command. Ensure that the initial switch port states are inactive with the shutdown command. Use the interfacerangecommand to simplify this task. Repeat these commands on each switch. Switch(config)#interface range fa0/1-24 Switch(config-if-range)#shutdown Switch(config-if-range)#interface range gi0/1-2 Switch(config-if-range)#shutdown

Task 2: Perform Basic Switch Configurations
Configure the S1, S2, and S3 switches according to the following guidelines: • • • • • Configure the switch hostname. Disable DNSlookup. Configure an EXEC mode password of class. Configure a password of cisco for console connections. Configure a password of cisco for vty connections.

(Output for S1 shown) Switch>enable Switch#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)#hostname S1 S1(config)#enable secret class S1(config)#no ip domain-lookup S1(config)#line console 0...