Every network has a network engineer who swears nothing changed, and a network that disagrees. This capstone builds the tool that settles the argument: an automated backup and drift detector that snapshots every device config to a golden baseline, re-checks the fleet on demand, and prints a unified diff of exactly what changed, on which device, with a nonzero exit code your scheduler can alarm on. It is the final lab of the PingLabz CCNA Automation Labs and it uses everything the series taught: Netmiko sessions (auto-01), device loops (auto-02), enable mode (auto-03), and a JSON inventory (auto-04). All output below is captured from the live CML Free lab.
This is also the point of the whole series, stated plainly: Domain 6 is not on the exam because Cisco wants you to recite "REST uses HTTP verbs." It is there because the working network engineer of the next decade keeps a tool like this one running against every network they touch.
What you will learn
- How to design a two-mode CLI tool (baseline / check) around the golden-config concept.
- How to strip volatile lines from a running config so diffs show real changes, not timestamp noise.
- How to produce unified diffs with Python's standard library and signal drift through exit codes.
- How this maps to the real-world practice the exam calls configuration drift and version control.
