Hosted agents that die uncleanly (kernel OOM kill, SIGKILL, whole-VM
death) leave no trace: shutdown_forensics only covers graceful signals,
gateway-exit-diag.log only covers exit paths that actually run, and the
VM reboot wipes dmesg before anyone can capture it. NS-608 (BlueAtlas
hourly crash cycle, July 12-15) took days of manual log correlation to
classify because nothing recorded 'the previous life ended violently'.
Add gateway/lifecycle_ledger.py — a sentinel state machine persisted to
<HERMES_HOME>/state/gateway.lifecycle.json:
- start_gateway() claims the sentinel (phase=running) right after the
PID-file/runtime-lock claim, and reports any prior life that never
reached an exit path as gateway.previous_unclean_exit in
gateway-exit-diag.log + a WARNING log line.
- Every exit funnel marks the sentinel exited with a reason:
_exit_after_graceful_shutdown (graceful_shutdown), the shutdown
watchdog (shutdown_watchdog), and the loop-liveness watchdog
(loop_liveness_watchdog).
- Ownership-guarded for --replace takeovers: a live matching owner is
never reported dead, and the old life cannot clobber the
replacement's freshly claimed sentinel on its way out.
The 30s loop heartbeat now embeds a cheap /proc memory sample (own RSS,
MemAvailable, swap used) so every unclean-death report carries a
'memory N seconds before death' snapshot; the detector flags
suspected_oom when the last sample shows <64MiB or <5% available.
container-boot.log lines gain prior_exit=clean|unclean|unknown per
profile, stamping unclean container deaths into the volume-persisted
boot log where support can grep for them.
Tests: tests/gateway/test_lifecycle_ledger.py (16 cases) + 4 new
container-boot annotation cases. Existing watchdog/forensics/boot
suites all green; ruff clean.
Shannon Sands
9c76c133b7