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How to Monitor Cron Jobs in Linux (2026 Guide)

Published March 2026 · 4 min read

Cron jobs fail silently. That's their biggest flaw. A job can stop running — bad path, disk full, permission error, server reboot — and you won't know until something downstream breaks.

This guide covers three approaches to monitoring cron jobs, from basic to bulletproof.

1. The DIY Approach: Log and Check

The simplest method is redirecting output to a log file and checking it:

0 2 * * * /usr/local/bin/backup.sh >> /var/log/backup.log 2>&1

Problems: you have to remember to check. Nobody does. You'll find out about failures when it's too late.

2. The Email Approach: MAILTO

Cron can email you when a job produces output:

[email protected]
0 2 * * * /usr/local/bin/backup.sh

Better, but only triggers on output — not on absence. If the job doesn't run at all (server was down, cron daemon crashed), you get nothing.

3. The Heartbeat Approach: Ping on Success

This is the reliable method. Instead of watching for failures, you watch for expected successes. Your job pings a monitoring service after completing successfully. If the ping stops arriving, you get alerted.

0 2 * * * /usr/local/bin/backup.sh && curl -fsS https://ping.trebben.dk/YOUR_SLUG

This catches every failure mode:

• Job errors out → no ping → alert
• Job doesn't run (server down) → no ping → alert
• Cron daemon crashes → no ping → alert
• Job hangs forever → no ping after grace period → alert

Setting Up Heartbeat Monitoring with CronPulse

1. Sign up free at cronpulse.trebben.dk
2. Create a monitor — name it, set the expected schedule (e.g., "every day"), set a grace period
3. Copy the ping URL and append it to your crontab entry with &&
4. Done. If the ping stops arriving, you'll get an email, Slack, webhook, or Telegram alert.

Integration Examples

Bash / Shell Script

# Ping only on success (exit code 0)
0 2 * * * /path/to/job.sh && curl -fsS https://ping.trebben.dk/YOUR_SLUG

Python

import urllib.request

def main():
    # Your job logic here
    pass

if __name__ == "__main__":
    main()
    urllib.request.urlopen("https://ping.trebben.dk/YOUR_SLUG")

Node.js

// At the end of your scheduled task
async function run() {
  // Your job logic here
  await fetch("https://ping.trebben.dk/YOUR_SLUG");
}
run();

Docker / Kubernetes CronJob

apiVersion: batch/v1
kind: CronJob
spec:
  schedule: "0 2 * * *"
  jobTemplate:
    spec:
      containers:
      - name: backup
        command: ["/bin/sh", "-c", "/backup.sh && curl -fsS https://ping.trebben.dk/YOUR_SLUG"]

Free Tier

CronPulse gives you 20 monitors for free — no credit card, no trial expiration. That's enough for most setups. Email, Slack, webhook, and Telegram alerts are all included.

Start monitoring your cron jobs — free

Built by Jeff in Denmark. See also: free developer tools.