Site-level cooling/power interruption in rack 0: nodes de-energized to PSU standby, fans stopped, and rack ambient rose +14.8 C above its 7-day baseline and held near 37.6 C
Co-moving evidence:
- ambient_avg — rack0-node16: 22.8 C baseline (7-day trailing median) -> 34.4 C within 1 h of event start (2022-07-04T18:00:00Z), peak 37.6 C through 2022-07-05T06:30:00Z; rack0-node8 peak 30.2 C; rack0-node9 peak 36.7 C
- fan0_0..fan3_1 (RPM) — all eight fan tachs read 0 RPM on rack0-node8 (51/70 reporting samples in the event window), rack0-node9 (4/20 reporting samples in the event window), rack0-node16 (51/70 reporting samples in the event window) against a per-tach baseline of ~4340-4700 RPM (n=44,024 readings outside the event) — cooling stopped, co-moving with the ambient rise. 0 RPM is a reading; NaN is absence, and NaN samples are excluded rather than read as zero
- ps0_input_power_avg / total_power_avg — rack0-node16 PSU input drops to 10 W standby and node total power reads NaN in 51 samples during the event (node de-energized); ~379 W median idle before and after
106/107 R6 detections fall inside Nagios CRITICAL windows; 0 detections in the quiet days of the slice; the 1 remaining detection precedes the first CRITICAL label by 15 min on this event (label lag, not a false positive; n=1, not a general capability claim)
A cooling/power interruption spanning 17.25 h across a 16-node rack; on this event, the rule tripped 15 minutes before the facility's first Nagios CRITICAL label (n=1 — the defensible claim is 106/107 label agreement and 0 quiet-day false positives)
- ambient 20.5–39.4 °C
- fan median 0–4,889 RPM
