DeadManPing Examples

Working code examples for backup dead man switch monitoring and cron job monitoring with DeadManPing.

This repository contains real-world examples in multiple languages showing how to:

• Detect empty backup files (zero bytes)
• Detect when backups don't run (dead man switch)
• Verify backup file sizes (payload validation)
• Detect silent cron failures
• Check exit codes and status
• Handle edge cases
• Monitor job execution

Quick Start

1. Sign up for DeadManPing (free account)
2. Create a monitor and get your ping URL
3. Copy an example script below
4. Replace YOUR_MONITOR_ID with your actual monitor ID
5. Add the script to your cron job

Examples by Problem

Backup Monitoring (Dead Man Switch)

Problem	Solution	Examples
Backup Didn't Run	Dead man switch detects missing backups	Bash | Python | Node.js
Detect Empty Backup File	Check if backup file is zero bytes	Bash | Python | Node.js
Detect Empty Backup File Cron	Check backup file size after creation	Bash | Python | Node.js
Backup File Zero Bytes	Detect empty backup files	Bash | Python | Node.js
Verify Backup File Size	Check backup file size ranges	Bash | Python | Node.js
Detect Backup File Missing	Verify backup file exists	Bash | Python | Node.js

Cron Job Monitoring

Problem	Solution	Examples
Curl Success But Wrong Response	Validate API response content	Bash | Python | Node.js
Silent Cron Failures	Explicit success confirmation with ping	Bash | Python | Node.js
Verify Cron Output	Validate script output content	Bash | Python | Node.js
Cron Job Exit Code Not Zero	Check and handle exit codes	Bash | Python | Node.js
Verify Cron Job Actually Ran	Confirm job execution with pings	Bash | Python | Node.js
Cron Job Returns Success But Fails	Validate results, not just exit codes	Bash | Python | Node.js
Cron Job Silent Failure Detection	Detect failures without logs	Bash | Python | Node.js
Curl Returns 200 But Wrong Data	Validate API response body	Bash | Python | Node.js
Detect Cron Job Partial Failure	Verify all steps complete	Bash | Python | Node.js
Detect Cron Job Wrong Exit Code	Validate exit codes	Bash | Python | Node.js
Verify Script Output Content	Check output contains expected data	Bash | Python | Node.js
Cron Job Not Executing	Detect when jobs don't run	Bash | Python | Node.js
Verify Cron Job Completed	Confirm job finished successfully	Bash | Python | Node.js
Detect Cron Job Skipped	Catch jobs that don't run	Bash | Python | Node.js
Cron Job Exit Status Check	Verify exit status codes	Bash | Python | Node.js

Examples by Language

• Bash Examples - Shell scripts for Linux/Unix systems
• Python Examples - Python scripts with error handling
• Node.js Examples - JavaScript/Node.js examples
• Cron Patterns - Example crontab entries
• Edge Cases - Advanced scenarios and rare cases

Documentation

Each example links to detailed documentation on deadmanping.com:

Backup Dead Man Switch

• Backup Dead Man Switch - Complete guide on backup dead man switch monitoring
• Backup Didn't Run - How to Detect - Detect when backup jobs don't run
• Detect Empty Backup File - How to detect zero-byte backup files
• Backup Monitoring Without Infrastructure - Monitor backups without Kubernetes/Prometheus
• Dead Man Switch for Backups - Dead man switch monitoring for backup jobs
• Backup Monitoring Service - Backup monitoring that doesn't touch your execution

Cron Job Monitoring

• Monitor Cron Jobs - Monitor cron jobs without migration
• Cron Job Failed - Detect and fix cron job failures

How It Works: Backup Dead Man Switch

DeadManPing uses a dead man switch pattern for backup monitoring:

1. Your cron job runs your backup script
2. Your backup script performs its work (rsync, database dump, etc.)
3. Your backup script sends a ping to DeadManPing when done (with backup data like file size)
4. If the ping doesn't arrive, you get an alert - backup didn't run or failed
5. DeadManPing validates backup data (file size, status) and alerts if backup is empty or incorrect

Important: The ping must be inside your backup script, not in the cron line, because only in the script do you have access to variables from execution results (e.g., backup file size, success status).

Example: If your backup script creates an empty file (0 bytes), DeadManPing detects this by validating the file size in the ping payload. If your backup script doesn't run at all, the ping never arrives, and DeadManPing alerts you.

Getting Your Ping URL

1. Sign up at deadmanping.com
2. Create a monitor
3. Copy your unique ping URL (format: https://deadmanping.com/api/ping/YOUR_MONITOR_ID)
4. Replace YOUR_MONITOR_ID in the examples with your actual monitor ID

Contributing

Found a bug or have a better example? Open an issue or submit a pull request!