IntermediatePublished 2026-08-28
CCNA Break/Fix: Translation Happens, Replies Do Not
Archive lab
Lab 5 of 7 in CCNA Break/Fix: Diagnose and Repair · ← Previous · Next →
CCNA exam domain: IP Services
A branch reaches its provider through one edge router that hides the user LAN behind its upstream address. Since a change window, everyone on 192.168.10.0/24 reports that nothing beyond the branch answers, while the router itself reaches the provider's test address. Find what is wrong.
Learning objectives
- Diagnose translation state from
show ip nat translationsandshow ip nat statistics. - Verify the selection ACL and default route an edge NAT depends on.
- Isolate the failing segment of the CLIENT01-to-198.51.100.100 path across RTR-EDGE-R1.
- Prove reachability from CLIENT01 and CLIENT02 to 198.51.100.100.
Troubleshooting focus
- CLIENT01 and CLIENT02 get no reply from 198.51.100.100; RTR-EDGE-R1 pings it without loss. Compare the paths, not the hosts.
- Each client reaches its gateway, 192.168.10.1. A LAN that reaches its own gateway clears VLAN 10, the access ports and SW-EDGE-ACC1.
- The translation table reads empty. Read it while a client is generating traffic. Entries are per-flow and age out in seconds, so a table read afterwards proves nothing.
Topology
Subscribe to preview this lab's topology.
See plansGrade 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.
- Scored something you believe is correct? Use Report an issue on this page — that is exactly how the grading fixes in the changelog got found.
Create a free account to submit your lab for grading.
Create a free accountFound a problem with this lab?
Please sign in to report a problem — tying it to your attempts lets us reproduce and fix it faster.