Chapter 13:
Outline of Chapter 13: Network Troubleshooting
Demonstrate the Ability to Troubleshoot the 5-Router Network
Explain the standard configuration.
Describe typical layer 1 errors.
broken cables
disconnected cables
cables connected to the
wrong ports
intermittent cable connection
wrong cables used for the
task at hand (must use
cross-connects, rollovers,
and straight-through cables correctly)
transceiver problems
DCE cable problems
DTE cable problems
devices turned off
Describe typical layer 2 errors.
improperly configured serial
interfaces
improperly configured
Ethernet interfaces
improper encapsulation set (HDLC is default)
improper clock rate settings on serial interfaces
Describe typical layer 3 errors.
routing protocol not enabled
wrong routing protocol enabled
incorrect IP addresses
incorrect Subnet Masks
incorrect DNS to IP bindings
Describe network troubleshooting strategies.
Use of Flow Charts
Use of other team members or experts, tools, ....