Oliver Kieselbach
04b1a7c6e7
Field regression, session e9753578 (agent 2.0.1410, PST-defaulted device in DE).
Five script_started events resolved 9 h early while their script_completed
counterparts resolved correctly, inflating every platform-script duration to
~32,400 s. Reverts the application introduced in e9dba11b.
Root cause: calibration keeps ONE offset per log file, but a single file can hold
lines from two writer eras. IME restarting across a timezone change leaves older
lines in the old zone and newer ones in the new zone, in the same file. The anchor
is the newest line, so its offset was also applied to the older lines, for which
it does not hold. The class doc even claimed "self-healing on writer restart" —
that reasoning only ever covered FUTURE lines, never the ones already on disk.
The more expensive mistake was the second one: correcting ABSOLUTE timestamps
without checking what depends on their DIFFERENCES. Applying the reader zone
uniformly is wrong in absolute terms but self-consistent — both ends of a duration
are wrong by the same amount, so the duration is right. Correcting only some
timestamps produced a mixed frame inside one session, which is strictly worse than
being uniformly wrong. This is the same asymmetry the original analysis described
for AppInstallSummaries (68 min reported against 8 min real) and then reproduced.
What stays, deliberately:
- Bias-carrying lines still resolve via the writer-declared offset; that path was
never implicated.
- The measurement keeps running. It costs nothing, feeds the Info log, and is the
field data the era-aware fix has to be built on — the first anlauf got the era
question wrong from assumption rather than observation.
- Provenance now separates measured from applied (measuredWriterOffsetMinutes vs
sourceOffsetMinutes). The broken event was tagged "calibrated" while carrying an
offset that did not hold for its line; that confusion must not be expressible.
- The fallback path reports the offset it actually applied. An event stating no
offset cannot be recomputed later, which defeats the point of provenance.
Provenance earned its keep here: 57 events measured -420 (the PDT writer) against
5 at +120 made the diagnosis a two-minute query instead of median statistics over
a session.
Next: era-aware calibration keyed on the IME-STARTED marker, which we already
track, plus a test over a log file containing two writer eras — the case that was
missing.
Agent 2393 green against a verified-clean build.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
AutopilotMonitor
Advanced monitoring and troubleshooting solution for Windows Autopilot deployments. Gain full visibility into every enrollment session with a detailed event timeline, fleet health dashboards, and session reporting. Define custom analysis rules to automatically detect issues and gather rules to collect targeted evidence. Retrieve diagnostics packages on demand, configure agent settings like auto-reboot behavior and automatic timezone adjustment — all managed centrally from the web dashboard.
Availability
Autopilot Monitor is publicly available — the Community plan is free. Sign in with your work account at autopilotmonitor.com; new organizations complete a short activation step after first sign-in.
Overview
Autopilot Monitor provides real-time tracking, intelligent diagnostics, and automated troubleshooting for Windows Autopilot enrollment processes. It consists of:
- Bootstrap Script — PowerShell script deployed via Intune that starts monitoring early in the enrollment process
- Monitoring Agent — Lightweight .NET application that collects telemetry and evidence during enrollment
- Backend API — Azure Functions-based ingestion and processing pipeline
- Web Dashboard — Next.js application for real-time monitoring and fleet analytics
Architecture
For detailed information about the system architecture, components, and data flow, see Architecture Documentation.
Documentation
Full admin documentation is available at docs.autopilotmonitor.com
License
This project uses a split licensing model:
- MIT License — Agent (
src/Agent/) and Shared library (src/Shared/) — unrestricted use on end-user devices - AGPL-3.0 — Backend (
src/Backend/), Web Dashboard (src/Web/), and MCP Server (src/McpServer/) — server-side components remain open source
See LICENSE for full details.