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AdvancedPublished 2026-06-25

CCNA Static Routing: Troubleshooting Broken Static Routes

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Hands-on CCNA static routing troubleshooting in a realistic three-router core/edge topology with two user LANs. Static routing on the network was recently changed and users at SITE-A (10.10.10.10) and SITE-B (10.30.30.10) can no longer reach each other; you will investigate the routers' route tables and next-hop reachability to diagnose and restore full bidirectional connectivity.

Track
Est. time
55 minutes
Difficulty
Advanced
Topics

Learning objectives

  • Identify and correct a static route with a wrong next-hop IP address.
  • Identify and repair a static route with an incorrect subnet mask that prevents route lookup.
  • Detect and fix a missing default route at the edge.
  • Diagnose and restore a missing return-path static route on the core that causes one-way ping failure.
  • Validate repairs using ping (with source), traceroute, and show ip route.

Troubleshooting focus

  • traceroute -n 10.30.30.10 from HOST-SITE-A-USER stalls at the first hop though the static route exists: its next-hop is RTR-SITE-A-EDGE's own transit address, so packets never leave. Point the static at 10.12.12.2.
  • ping -c 3 10.10.10.10 from HOST-SITE-B-USER reports no route to host: the static route's prefix does not cover the destination.
  • Traffic matching no specific route is dropped locally on RTR-SITE-B-EDGE: the edge has no default.
  • One direction works but the replies die at RTR-CORE: the core has no return path. Add a specific static on RTR-CORE for each edge LAN via the appropriate transit neighbour.
  • Reachability improves but is still not end-to-end: re-run ping and traceroute from both hosts after each fix — one repaired fault can mask another.

Topology

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Study this topic

Free guides, a command cheat sheet, and graded practice for this lab's topic.

Learn Static & Default RoutingHow Does Routing Work? The Routing Table Explained

Grade your work

How this lab is graded
  • Build it your way. Where a lab lets you choose a value — a VLAN name, an interface description — grading checks that you configured it, not which name you picked. Names that another line has to reference, like an ACL applied with access-class, are stated in the guide and do have to match.
  • Addresses, modes and protocol keywords are exact. An IP address, a subnet mask, switchport mode trunk, an encapsulation — these carry the meaning of the lab, so they are graded as written in the guide.
  • Grading reads your saved configuration. Export the lab from CML after you have configured it, and make sure anything you set is in the running-config — a change that only exists in a terminal session never reaches the grader.
  • You can submit as many times as you like. Your best score stands, and each attempt tells you which checks passed so you can work the gaps.
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