← Documentation: Reliable Backup & Sync Execution Validation (Log-Driven)
The monitor combines two kinds of evidence: GitHub says which logs should exist, and GCS supplies the logs that actually arrived. The backup script and uploader operate outside n8n.
Presence checks compare the GCS listing with the manifest. Available logs then enter deterministic parsing and AI analysis. Gmail alerts identify the relevant kind of problem rather than treating every present file as a successful backup.
The supplied job scripts emit lifecycle markers such as:
event=START
event=RSYNC_END rc=0
event=SUMMARY rc=0 errors=0 warnings=0
event=END rc=0 duration_s=42 status=OK
Use RCLONE_END for rclone. The final END records completion; a missing marker is an incomplete execution. Capture the backup command's actual exit code, including on failure.
Logs are uploaded under:
gcs:YOUR_BUCKET/sync-logs/YOUR_HOST/YYYY/MM/DD/*.log
The uploader destination and n8n's Set_Prefix must agree exactly. The date path uses UTC, while the scheduling rules also use local time. Configure both deliberately in 02 · Installation & Configuration.