Trunking Misconfiguration (Troubleshooting LAN Switches)

Lab 6.2.2 Trunking Misconfiguration Troubleshooting LAN Switches Fa 0/2 Trunk Crossover Connection ALSwitch 2900XL-Ent VLAN 10 Client Objective Trunking changes the formatting of the p

Lab 6.2.2 Trunking Misconfiguration (Troubleshooting LAN

Switches)

Fa 0/2 Trunk

Crossover Connection

ALSwitch

2900XL-Ent

VLAN 10 Client

Objective

Trunking changes the formatting of the packet The ports need to be in agree-ment as to what format they are using on the link or they will not understand each other If you turn the trunking mode to on (as opposed to auto or desir-able) for one port and the other port has the trunking mode set to off, they will not be able to communicate

Scenario

This is not part of the International Travel Agency network

As the Enterprise Network Administrator, you add a new access layer switch to the network You establish trunking using the command “switchport mode trunk” on interface FastEthernet 0/1 for the access layer switch and establish the necessary VLAN trunking parameters for VTP The message “02:18:24:

%LINK-4-ERROR: FastEthernet0/1 is experiencing errors” appears on

ALSwitch

Lab Tasks

Clear the DLRouter configuration using the following commands:

Router#erase start

Erasing the nvram filesystem will remove all files! Continue? [confirm]y[OK]

Erase of nvram: complete

Router#reload

Proceed with reload? [confirm]y

Clear the DLSwitch configuration using the following commands:

Console> (enable) clear config all

This command will clear all configuration in NVRAM

This command will cause ifIndex to be reassigned on the next system startup

Do you want to continue (y/n) [n]? y

2001 Jun 16 12:29:45 %PAGP-5-PORTFROMSTP:Port 2/1 left bridge port 2/1

.2001 Jun 16 12:29:45 %PAGP-5-PORTFROMSTP:Port 2/2 left bridge port 2/2

2001 Jun 16 12:29:45 %PAGP-5-PORTFROMSTP:Port 2/3 left bridge port 2/3

Console> (enable) reset

This command will reset the system

Do you want to continue (y/n) [n]? y

Clear the ALSwitch configuration and VLAN database using the following com-mands:

ALSwitch#clear start

Erasing the nvram filesystem will remove all files! Continue? [confirm]y[OK]

Erase of nvram: complete

ALSwitch#delete vlan.dat

Delete filename [vlan.dat]?

Delete flash:vlan.dat? [confirm]y

ALSwitch#reload

Proceed with reload? [confirm]y

Load the file called Lab6-2-2-DLSwitchBrokenConfig.txt into the DLSwitch Load the file called Lab6-2-2-ALSwitchBrokenConfig.txt into the ALSwitch

Step 1

Define your problem

Step 2

Gather the Facts

On the DLSwitch:

DLSwitch> (enable) show trunk 2/3

* - indicates vtp domain mismatch

Port Mode Encapsulation Status Native vlan

- - - - -

2/3 on dot1q trunking 1

Port Vlans allowed on trunk

- - 2/3 1-1005

Port Vlans allowed and active in management domain

- - 2/3 1,10,20,30

Port Vlans in spanning tree forwarding state and not pruned

- - 2/3 1,10,20,30

On the ALSwitch:

00:15:01: %LINK-4-ERROR: FastEthernet0/1 is experiencing errors

ALSwitch#show vlan

VLAN Name Status Ports

- - -

1 default active Fa0/2, Fa0/3, Fa0/4, Fa0/5,

Fa0/6, Fa0/7, Fa0/8, Fa0/9,

Fa0/10, Fa0/11, Fa0/12

1002 fddi-default active

1003 token-ring-default active

1004 fddinet-default active

1005 trnet-default active

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

- - - - - - - - -

1 enet 100001 1500 - - - - - 1002 1003

1002 fddi 101002 1500 - - - - - 1 1003

1003 tr 101003 1500 1005 0 - - srb 1 1002

1004 fdnet 101004 1500 - - 1 ibm - 0 0

1005 trnet 101005 1500 - - 1 ibm - 0 0

Step 3

Write down your observations for the ALSwitch and the DLSwitch

Step 4

List the possible causes of this problem

Step 5

Create an action plan to fix the problem

Step 6

Implement the action plan

Step 7

Observe the results of the action plan

Step 8

Document your work