The router at my salon suite location crashed about once a week. Every time, the Wi-Fi died, everything downstream got flaky, and somebody had to drive over and pull the plug. The integrator who installed the network had stopped answering, so the fix was becoming a standing appointment: drive over, unplug, count to ten, drive home.

The smoke detector with no battery

So I took over the network myself. First visit, I found a WattBox — a smart power strip designed to detect a dead internet connection and power-cycle the router automatically — already installed, sitting right there in the rack. It had never been turned on. Somebody bought the smoke detector and never put the battery in. I enabled it, and the weekly outage went from hours-or-days to about six minutes, before anyone could text me.

But that was treating the symptom. The router was still crashing, and I wanted to know why.

Four wrong theories

Here’s where I embarrass myself: I tested five theories and four were wrong. The leading suspect for two full weeks was leftover VPN tunnels from the old setup — a guess based entirely on the previous integrator’s reputation, which I’d written down so confidently that I later treated my own hunch as an established fact. When I finally checked, the VPN page was empty. Zero tunnels. There had never been any tunnels.

Negative 106 million seconds

The real answer was sitting in the router’s system log, which holds all of fifty lines and wipes itself on every reboot. One of those fifty lines said the router had gotten its internet lease with a renewal scheduled in negative 106,633,522 seconds.

Negative 3.4 years. That’s not a typo, that’s a time traveler.

The router had no clock battery. Every cold boot, its clock fell back to roughly 1980, and it fetched an internet lease before syncing the actual time. Do the lease math from 1980 and you get a negative renewal, which sent the router into a confused loop that restarted every internal service in a cascade until the admin interface wedged itself completely. Every power cycle rolled the same dice. By the night I figured this out, it had degraded from weekly to hourly, and I got to watch it happen live, twice, like a nature documentary.

The impossible $2 fix

The fix was a $2 coin battery. I drove over with one, opened the case, and found there was no battery in the router — and no battery holder either. The board had a labeled spot where one should live and nothing to put it in. The $2 fix was physically impossible.

Fortunately I’d ordered a $199 UniFi gateway the night before, on the theory that hardware plans deserve a plan B. Swapped it in with about fifteen minutes of downtime. Within the hour, the new box had already flagged a bonus problem the old one was too far gone to notice: two digital signage players had been configured with the same IP address and were quietly fighting over it, probably for years.

The salon network has been boring ever since, which is the whole point. The short version of this story lives on the work page; this is the long version, mostly so I never again trust a diagnosis whose only source is me, two weeks ago, guessing.