The Loaner That Won't Reach the Internet

You help run the tiny office at the Cedar Hollow Community Garden. A volunteer carried over a spare laptop, garden-loaner, from the downtown branch so people can sign up for plots online. On the garden's home-office network it gets no internet at all. The office desktop, office-desk, works fine on the same router, hollow-gw.

Work the problem with the methodology: gather information, compare the broken host to the working one, form a theory, fix it, then verify. Pick a host below, read its settings, and use the command line. Tasks tick off as you go.