Wi-Fi Signal Needed a Fallback Path

The host collector originally relied on iw, but driver and interface behavior did not always expose the active connection signal consistently. I ended up treating hserver_wifi_signal_dbm plus hserver_wifi_signal_percent from nmcli as the useful observation point rather than relying on a generic service-up indicator. Using both low-level radio data and NetworkManager's active-network view made the signal metric more robust without pretending the two scales are identical.

This is a good example of defensive telemetry collection. The purpose is to reduce ambiguity during an incident: a signal should tell me which layer to inspect next, not simply confirm that something somewhere looks unusual.

For production I use the following guardrail: Collect dBm when available, expose percentage as a separate metric, and make missing data visible rather than silently substituting one unit for another. The same rule keeps the dashboard useful when the system grows and more targets are added.

The implementation is traceable to 218300b in the hserver repository. That commit is the concrete reference for the collector, alert, dashboard, or runtime change behind this article.