Troubleshooting LAN Switching

hellhollowreadingNetworking and Communications

Oct 26, 2013 (3 years and 8 months ago)

101 views

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© 2003, Cisco Sy stems, Inc. All rights reserv ed.

Computer Networks 6

Layer 2 troubleshooting

Halmstad University

Olga Torstensson

035
-
167575
olga.torstensson@ide.hh.se


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Module 4

Troubleshooting Layer 2


Data Link Layer Problems


LAN Switching


Frame Relay


ISDN


PPP

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Symptoms of Data Link Layer Problems

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High Layer Protocol Failure

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PING to find Boundary of Problem

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Examine Line Status

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Suboptimal Traffic Flow

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Intermittent Packet Loss

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Interface Encapsulation

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Troubleshooting LAN Switching

Review

theory :STP VTP

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Don’t configure VTP servers off
-
line


VTP
advertisement revision may cause
problems in the domain


vtp
-

domain, mode, password

show vlan, show vtp domain, show vtp
statistics

show vtp status, show vtp counters


Troubleshooting VTP

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Show vtp status

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Characteristics of STP Failure & Switching
Loops

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STP

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Show spanning
-
tree

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Troubleshooting LAN Switching


show vlan
,
show spanning
-
tree
,



debug vlan packet


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Misconfigured EtherChannel