Terminal.skills
Skills/cron
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cron

Schedule recurring tasks with cron on Linux/macOS. Use when a user asks to run scripts on a schedule, set up automated backups, schedule data processing, or configure periodic tasks on a server.

#cron#scheduling#automation#linux#tasks
terminal-skillsv1.0.0
Works with:claude-codeopenai-codexgemini-clicursor
Source

Usage

$
✓ Installed cron v1.0.0

Getting Started

  1. Install the skill using the command above
  2. Open your AI coding agent (Claude Code, Codex, Gemini CLI, or Cursor)
  3. Reference the skill in your prompt
  4. The AI will use the skill's capabilities automatically

Example Prompts

  • "Deploy the latest build to the staging environment and run smoke tests"
  • "Check the CI pipeline status and summarize any recent failures"

Information

Version
1.0.0
Author
terminal-skills
Category
DevOps
License
Apache-2.0

Documentation

Overview

cron is the standard Unix task scheduler. Define schedules with cron expressions (minute, hour, day, month, weekday) to run scripts automatically. Used for backups, log rotation, data sync, health checks, and any recurring task.

Instructions

Step 1: Crontab Basics

bash
# Edit your crontab
crontab -e

# Format: minute hour day month weekday command
# ┌─── minute (0-59)
# │ ┌─── hour (0-23)
# │ │ ┌─── day of month (1-31)
# │ │ │ ┌─── month (1-12)
# │ │ │ │ ┌─── day of week (0-7, 0=Sun)
# │ │ │ │ │
# * * * * * command

Step 2: Common Schedules

bash
# Every day at 3 AM
0 3 * * * /opt/scripts/backup.sh

# Every hour
0 * * * * /opt/scripts/health-check.sh

# Every 15 minutes
*/15 * * * * /opt/scripts/sync-data.sh

# Monday to Friday at 9 AM
0 9 * * 1-5 /opt/scripts/daily-report.sh

# First day of every month at midnight
0 0 1 * * /opt/scripts/monthly-cleanup.sh

# Every Sunday at 2 AM
0 2 * * 0 /opt/scripts/weekly-maintenance.sh

Step 3: Best Practices

bash
# Always redirect output to a log file
0 3 * * * /opt/scripts/backup.sh >> /var/log/backup.log 2>&1

# Use full paths (cron has minimal PATH)
0 * * * * /usr/bin/node /opt/app/scripts/job.js

# Set environment variables
MAILTO=admin@example.com
PATH=/usr/local/bin:/usr/bin:/bin
SHELL=/bin/bash

0 3 * * * /opt/scripts/backup.sh

Step 4: System Cron (root tasks)

bash
# /etc/cron.d/app-maintenance — System-level cron file
SHELL=/bin/bash
PATH=/usr/local/bin:/usr/bin:/bin

# Database backup as postgres user
0 3 * * * postgres pg_dump myapp > /backups/myapp-$(date +\%Y\%m\%d).sql

# Log rotation
0 0 * * * root /usr/sbin/logrotate /etc/logrotate.conf

Guidelines

  • Always use full paths in cron — the PATH is minimal.
  • Redirect output to log files or /dev/null — unhandled output gets emailed.
  • Use crontab -l to list, crontab -e to edit, crontab -r to remove all (careful!).
  • For modern alternative with dependency tracking, use systemd timers.
  • Test commands manually before putting them in cron.