← incident filesTKT-60012 · MT Quillon · T-1003 · opened 14 Oct 2026, 03:40 UTC

Rain fade

MONMonitorS4Regional85% confidence
Customer report
MT Quillon

“Internet keeps dropping since the technician visited last week. We think the antenna was installed wrong, please send someone back.”

Diagnosis

The outage was an atmospheric fade on beam B1. Es/No fell gradually from about 10.7 dB at 02:00 to 0.2 dB. Rx lock was lost 02:55–03:15 and then recovered with the weather. Pointing, BUC and GPS are normal, so this is not an installation or antenna mispoint problem, and no technician visit is needed.

T-1003
Evidence
  1. modem.log: esno falls 10.2 dB (02:00) to 1.6 dB (02:50), ACM steps 8PSK-3/4 to QPSK-1/2 to QPSK-1/3, rx lock lost 02:55:42 and reacquired 03:15:19; esno 10.1 dB on 8PSK-3/4 by 03:45
  2. acu.log: point_err stays 0.01–0.17 deg throughout, state=TRACKING; signal sags 74% to 37% and recovers to 71%, which is the fade pattern and not a pointing error
  3. After the 02:35 ACU restart, acu.log shows 'acquisition complete, locked on beacon peak_sig=74%', so pointing was re-acquired correctly
  4. Fleet: other B1 terminals dipped in the last 2h (T-1001 min 5.0, T-1002 min 3.6, T-1009 min 6.8, T-1003 min 0.2) while distant beams are normal. T-1002 fades at a different time (its log is on a different clock), as expected for rain
  5. system.log: buc_current 1.74–1.86 A, buc_temp 39–44 C, GPS 3D fix 7–11 sats, mem 33–39 %, uptime 11d, so no BUC, GPS or reboot fault
  6. Config check: network, qos and terminal conf are identical to last-known-good. show/network.log: lan0 up throughout; wan=down only 02:55–03:10 during the lock loss
  7. Now: T-1003 esno_now 10.1 vs 24h avg 11.0, fwd 4.83 Mbps, reboots_24h 0
Other findings
T-1003Outside the known fault listsystem.log 02:35:17 shows 'ODU supply interruption (input 0V for 2.3s)' and acu.log 02:35:22 shows a controller restart after power loss. The ACU recovered within about 3 minutes and did not cause the outage, but a recurrence could point to the ODU power connection from the recent install. Escalate to a technician check if it repeats.MONMonitor
T-1031Not enough evidence yetT-1031 (B4) has been offline with TERMINAL_UNREACHABLE since 2026-10-11T17:48Z. The cause is unknown. Check hub-side logon and last logs, and check whether it has power or LAN.DATCollect more data
Evidence gaps
  1. No weather data to confirm rain directly; the fade is inferred from the Es/No and signal profile and from the neighbouring B1 terminals.
  2. Only about 7h of logs are available, so there is no history to test the claim that drops have continued since last week's visit.
Next steps
  1. Tell the customer the drop at 02:55–03:15 UTC was a weather fade and that service is restored. The antenna is pointing correctly (error ~0.1 deg).
  2. Do not dispatch a technician. Watch T-1003 for repeat dips or lock losses in clear weather.
  3. If another ODU supply interruption occurs, ask for the ODU power cable and connections to be inspected at the next visit.
  4. Check T-1031 separately: hub-side logon status and last-seen data.
Investigation

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