Video summary

Free CCNA | Troubleshooting Static Routes | Day 11 Lab 2 | CCNA 200-301 Complete Course

Main summary

Key takeaways

Technology

Tech Concepts & Troubleshooting Workflow (CCNA Static Routes)

Lab goal

Troubleshoot why PC1 cannot ping PC2 in a previously built topology. The lab rules state there is exactly one misconfiguration per router.

Initial problem confirmation

  • Verify the connectivity failure by attempting a ping between PCs: PC1 → PC2

PC-side verification commands (Windows)

  • ipconfig — check IP address, subnet mask, default gateway
  • ipconfig /all — get more detail including MAC address
  • Validate that PC can reach the default gateway:
    • ping <gateway IP>
    • (Gateway reachability is confirmed.)

R1 Troubleshooting: Static Route Next-Hop Error

Check interface status

  • show ip interface brief
    • Interfaces are UP/UP
    • Interface configuration is correct

Inspect routing table

  • show ip route
    • A static route exists for 192.168.3.0/24, but the next-hop IP is wrong
      • Configured next hop: 192.168.12.3
      • Correct next hop should be: 192.168.12.2 (R2’s G0/0)

Fix method (modify the static route)

  1. Locate the incorrect route:
    • show running-config | include ip route
  2. Enter config mode and delete the incorrect route:
    • no <ip route ...>
  3. Re-add the corrected route with the updated next-hop:
    • Change next hop from ...3 → ...2

Verify

  • Re-check routing:
    • show ip route
    • Confirm the corrected static route is present.

R2 Troubleshooting: Wrong Exit Interface + Route Behavior

Interface check

  • show ip interface brief
    • All interfaces are UP/UP

Routing table inspection

  • show ip route
    • Two expected static routes exist
    • Problem: to reach 192.168.3.0/24, R2 uses the wrong exit interface
      • Uses g0/0, but should use g0/1

Demonstration: Keeping both routes

  • The instructor adds the correct route without removing the incorrect one.
  • show ip route shows both routes remain.
  • Explanation: having both routes can lead to load-balancing, sending traffic out either G0/0 or G0/1—undesirable since G0/0 is wrong.

Fix

  • Remove the incorrect static route statement using:
    • no ...
  • Verify that only the correct route remains.

R3 Troubleshooting: IP Addressing Error Causing Static Route Dependency Issues

Interface check

  • show ip interface brief
    • Misconfiguration found on G0/0
      • Should be 192.168.13.3
      • Currently is 192.168.23.3

Fix approach for interface IP

  1. Enter interface configuration mode:
    • conf t
    • interface g0/0
  2. Apply the corrected IP:
    • The new IP overwrites the existing IP
    • Deletion (using no) is not required in this case

Verification

  • Confirm routing table shows a static route to 192.168.1.0/24:
    • Via 192.168.13.2 (R2)
  • This validates that the dependent routing behavior is now correct.

Final Verification (End-to-End)

  • After fixing the misconfigurations on R1, R2, and R3, the instructor repeats:
    • Ping from PC1 to PC2
  • Note: the first one or two pings may fail, but connectivity succeeds once routing/addressing is corrected.

Tutorial / Lab Emphasis

Recommended: build and troubleshoot the lab yourself first to develop troubleshooting skills instead of watching for answers.

Key command set demonstrated for static route troubleshooting:

  • ipconfig
  • ping
  • show ip interface brief
  • show ip route
  • show running-config | include ip route

Corrective configuration patterns shown:

  • Use no to remove incorrect static routes
  • Fix interface addressing by overwriting the IP when appropriate

Main speaker / Source

Jeremy’s IT Lab (Jeremy’s teaching and explanation throughout the lab)

Original video