Grading Checklist

• Uses journalctl -u data-sync --no-pager -n 50 to read service logs and identify the exit reason.
• Examines the systemd unit file to understand the service configuration.
• Identifies the root cause: missing environment variable or config file that exists in dev but not in prod.
• Explains the start-limit-hit mechanism: systemd stops restarting after StartLimitBurst attempts within StartLimitIntervalSec.
• Shows how to reset the failure counter: systemctl reset-failed data-sync.
• Explains the difference between the service running as root (manual) vs. a service user (systemd).
• Checks for permission issues: file access, port binding, directory creation.
• Recommends using systemd-analyze verify to check the unit file for errors.
• Suggests adding RestartSec=5s to add delay between restarts and avoid hitting the rate limit so quickly.
• Mentions debugging with systemd-run to test the exact environment systemd provides.
• Notes that Environment= or EnvironmentFile= in the unit file is needed for production config.
• Recommends checking Type= is correct (simple, forking, notify, etc.) for the application's behavior.