Best Practices
Cron Best Practices
Cron is simple, but production schedules need guardrails. Good logging, timezone awareness, and failure handling prevent quiet outages.
Production habits
- Avoid jobs that run more often than the work can finish.
- Write logs for every scheduled run.
- Use absolute paths for commands and files.
- Set explicit environment variables instead of relying on shell defaults.
- Test expressions before production changes.
Reliability patterns
- Prevent overlapping jobs with locks or platform concurrency controls.
- Monitor failures and missed runs.
- Use retries for transient network or service errors.
- Document timezone assumptions near the schedule.
0 2 * * * /usr/local/bin/backup.sh >> /var/log/backup.log 2>&1Common mistakes
- Running jobs every minute without checking duration.
- Depending on relative paths.
- Ignoring daylight saving time and timezone changes.
FAQ
How do I prevent overlapping cron jobs?
Use a lock file, a queue, or a platform feature such as Kubernetes CronJob concurrencyPolicy.
Should cron jobs log output?
Yes. Logs are often the fastest way to debug missed runs, permissions, and environment issues.