Episode 22 — Network troubleshooting workflow: link → IP → route → DNS → service bind
Linux+ network questions are easier when you use a consistent workflow that prevents you from skipping layers. This episode teaches the link → IP → route → DNS → service bind sequence as a repeatable diagnostic path: confirm the interface is up and negotiating correctly, confirm the host has a valid IP configuration, confirm routing can reach the target network, confirm name resolution returns the expected address, and finally confirm the application is actually listening on the correct interface and port. The exam often provides partial evidence—one command output or one error message—and expects you to infer the next best step, so the value here is knowing what must be true before the next layer can work. You’ll learn to treat each layer as a gate, and to avoid wasting time debugging DNS when the link is down.
we expand the workflow with realistic scenarios and troubleshooting judgment. You’ll practice distinguishing local-only failures (the service is not bound, firewall blocks local traffic, wrong interface) from upstream failures (default route missing, gateway unreachable, DNS points to wrong address). We also cover ambiguity patterns common in PBQs, such as a system that can ping an IP but not a hostname, or a hostname that resolves but connections still fail because the service is bound only to localhost. Finally, you’ll learn best practices for speed and safety: make the smallest test that proves a layer, document what you changed, and revert temporary fixes that could mask the root cause, so your final state is stable and explainable. Produced by BareMetalCyber.com, where you’ll find more cyber audio courses, books, and information to strengthen your educational path. Also, if you want to stay up to date with the latest news, visit DailyCyber.News for a newsletter you can use, and a daily podcast you can commute with.
