15 Useful Cron Jobs for Web Developers

Cron is the foundation of server automation. This article contains 15 ready-made jobs for common web development tasks: backups, cache cleanup, sending reports, and synchronization. Each job can be copied and adapted. To generate and validate schedules, use the Cron Generator on reChecker. The basic cron syntax is described in the cron jobs guide.

1. MySQL backup

A daily database dump at 3:00 with rotation of old copies:

0 3 * * * /usr/bin/mysqldump -u backup -p'password' --single-transaction --routines --triggers mydb | gzip > /backups/mydb_$(date +\%Y\%m\%d).sql.gz

Rotation—deleting dumps older than 7 days:

0 4 * * * find /backups -name "mydb_*.sql.gz" -mtime +7 -delete

In crontab, the % character must be escaped: \%.

2. PostgreSQL backup

0 3 * * * /usr/bin/pg_dump -U postgres mydb | gzip > /backups/mydb_$(date +\%Y\%m\%d).sql.gz

Configured using .pgpass (a file with permissions 600):

0 3 * * * /usr/bin/pg_dump -U postgres -h localhost mydb | gzip > /backups/mydb_$(date +\%Y\%m\%d).sql.gz

3. Website file backup

Archive a directory with exclusions:

0 2 * * 0 tar -czf /backups/site_$(date +\%Y\%m\%d).tar.gz -C /var/www --exclude='*/cache/*' --exclude='*/logs/*' example.com

Weekly on Sunday at 2:00. Cache and logs are excluded.

4. Log cleanup

Rotate and delete old application logs:

0 0 * * * find /var/www/example.com/storage/logs -name "*.log" -mtime +30 -delete

Delete old Nginx/Apache logs (if logrotate is not used):

0 1 1 * * find /var/log/nginx -name "*.gz" -mtime +90 -delete

5. Temporary file cleanup

0 4 * * * find /tmp -type f -atime +7 -delete
0 4 * * * find /var/www/*/storage/framework/cache -type f -mtime +1 -delete

The first line removes general temporary files older than 7 days. The second clears the Laravel cache (adapt the path).

6. WordPress: updates and optimization

Use WP-CLI to update and optimize the database:

0 4 * * 0 cd /var/www/wordpress && wp core update --quiet && wp plugin update --all --quiet && wp db optimize --quiet

Weekly on Sunday at 4:00. Add --path=/path/to/wordpress if needed.

7. WordPress: backup with WP-CLI

0 3 * * * cd /var/www/wordpress && wp db export - | gzip > /backups/wp_$(date +\%Y\%m\%d).sql.gz

8. Laravel: scheduler

Laravel uses a single cron entry for the entire schedule:

* * * * * cd /var/www/laravel && php artisan schedule:run >> /dev/null 2>&1

Tasks are defined in app/Console/Kernel.php:

protected function schedule(Schedule $schedule)
{
    $schedule->command('backup:run')->daily()->at('03:00');
    $schedule->command('queue:prune-failed')->daily();
    $schedule->command('cache:prune-stale-tags')->hourly();
}

9. PHP session cleanup

Old sessions in /var/lib/php/sessions:

0 5 * * * find /var/lib/php/sessions -type f -mmin +1440 -delete

Sessions older than 24 hours (1440 minutes) are deleted. Configure this to match session.gc_maxlifetime in php.ini.

10. SSL certificate check

Send a notification 14 days before expiration (using certbot or openssl):

0 9 * * * /opt/scripts/check-ssl.sh

Example script:

#!/bin/bash
DOMAIN="example.com"
EXPIRY=$(echo | openssl s_client -servername $DOMAIN -connect $DOMAIN:443 2>/dev/null | openssl x509 -noout -enddate | cut -d= -f2)
EXPIRY_EPOCH=$(date -d "$EXPIRY" +%s)
NOW_EPOCH=$(date +%s)
DAYS_LEFT=$(( (EXPIRY_EPOCH - NOW_EPOCH) / 86400 ))
if [ $DAYS_LEFT -lt 14 ]; then
  echo "SSL истекает через $DAYS_LEFT дней" | mail -s "SSL Alert" admin@example.com
fi

11. Synchronization with remote storage

Upload backups to S3 or another object storage service:

0 5 * * * /usr/bin/aws s3 sync /backups s3://my-bucket/backups/ --delete

With encryption and a time limit (rclone):

0 5 * * * rclone sync /backups remote:backups --max-age 7d

12. Docker cleanup

Remove unused images and containers:

0 6 * * 0 docker system prune -af --volumes

Weekly. Make sure important volumes will not be deleted. A gentler option without --volumes:

0 6 * * 0 docker image prune -af && docker container prune -f

13. Send a website status report

Check availability and send a report:

0 9 * * 1-5 /opt/scripts/uptime-report.sh

The script can use curl to check HTTP and send the result by email or messenger.

14. Clear the mail queue (mailq)

If email is sent through a local MTA:

0 2 * * * find /var/spool/mail -type f -mtime +7 -delete

For Postfix—flush stuck messages (use with caution):

0 3 * * * postsuper -d ALL deferred

Use only if you understand the consequences.

15. Generate a sitemap

For static websites or custom CMSs:

0 6 * * * /usr/bin/php /var/www/example.com/generate-sitemap.php

Or use curl to call an internal endpoint:

0 6 * * * curl -s -o /dev/null https://example.com/cron/generate-sitemap?key=SECRET

The endpoint must be protected with a secret key and inaccessible from outside.

General recommendations

Example with a lockfile and logging:

0 3 * * * flock -n /tmp/backup.lock /opt/backup.sh >> /var/log/backup.log 2>&1 || echo "Backup already running" | mail -s "Cron alert" admin@example.com

The basic syntax and debugging of cron are described in the cron jobs guide. You can check and generate a schedule with the Cron Generator on reChecker.

Additional scenarios

Clean up old Laravel sessions

0 4 * * * find /var/www/*/storage/framework/sessions -type f -mmin +10080 -delete

Delete sessions older than 7 days (10080 minutes). Adapt the path to your project structure.

Synchronize with a remote repository

0 2 * * * cd /var/www/example.com && git pull origin main 2>&1 | logger -t git-sync

Update the code daily. Logs are written to syslog with the tag git-sync.

Check website availability

*/5 * * * * curl -sf -o /dev/null https://example.com/health || echo "Site down" | mail -s "Uptime alert" admin@example.com

Every 5 minutes. If the site is unavailable, send an email. For production, specialized monitoring services are preferable.

Docker cleanup

0 6 * * 0 docker image prune -af && docker container prune -f

Weekly removal of unused images and containers. Without -f, confirmation will be required.

Integration tips

When working with cron and web applications:

1. Use queues — for heavy tasks (email campaigns, reports), it is better to enqueue them (Redis, RabbitMQ) and process them with workers. Cron only adds the tasks.
2. Secure cron endpoints — if a task is called over HTTP, use a secret key in the URL and check the IP.
3. Document jobs — at the beginning of crontab or in a separate file, describe the purpose of each job.

Summary

15 ready-made jobs cover the main scenarios: backups, cleanup, updates, and monitoring. Adapt paths and parameters to your infrastructure. Test scripts manually before adding them to cron.