Summary
An understanding of the following key points should have been achieved:
  • The show ip route command
  • Determining the gateway of last resort
  • Determining the route source and destination address
  • Determining route administrative distance
  • Determining route metric
  • Determining route next hop
  • Determining last route update
  • Observing multiple paths to destination
  • Using a structured approach to troubleshooting
  • Testing by OSI layers
  • Layer 1 troubleshooting using indicators
  • Layer 3 troubleshooting using ping
  • Layer 7 troubleshooting using Telnet
  • Troubleshooting Layer 1 using show interfaces
  • Troubleshooting Layer 2 using show interfaces
  • Troubleshooting using show cdp
  • Troubleshooting using traceroute
  • Troubleshooting routing issues using show ip route and show ip protocols
  • Troubleshooting using show controllers serial
  • Troubleshooting using debug commands