Guides 7 min read
SSL Certificate Errors Explained: Causes and Fixes
NET::ERR_CERT_DATE_INVALID, ERR_CERT_COMMON_NAME_INVALID and the other browser SSL warnings explained: what each one means, what causes it and how to fix it on your server.
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Step-by-step guides to monitoring websites, APIs, cron jobs, SSL certificates, DNS and servers, with checklists you can apply to your own setup today.
Guides 4 min read
SSL Certificate Monitoring: Never Miss a Renewal Again
An expired SSL certificate turns your site into a browser warning. Why certificates still expire with auto-renewal, what to monitor and how to set reminders that work.
ReadGuides 7 min read
HTTP Status Codes Cheat Sheet for Website Monitoring
Which HTTP status codes mean your site is down, which are fine and which depend on the endpoint. A monitoring-focused cheat sheet covering 1xx to 5xx, redirects, 401, 403, 429 and 5xx errors.
ReadGuides 5 min read
How to Monitor Cron Jobs with Heartbeats
Cron jobs fail silently. A heartbeat monitor alerts you when a scheduled job does not check in on time. How heartbeats work, how to add one to a crontab and which settings to choose.
ReadGuides 8 min read
503 Service Unavailable: What It Means and How to Fix It
A 503 Service Unavailable error means the server is reachable but cannot handle the request right now. The common causes, how to fix each one and how monitoring catches 503s early.
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Cron Expressions Explained: Syntax, Examples and Common Mistakes
A cron expression is five fields that say when a job runs. The syntax, special characters and @daily shortcuts, ready-to-use examples and the timezone and PATH mistakes that break jobs.
ReadGuides 4 min read
What Is Uptime Monitoring? How It Works and What 99.9% Really Means
Uptime monitoring checks your website or API on a schedule and alerts you when it fails. How checks work, which interval to choose and what uptime percentages mean in minutes.
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Protect Your Online Presence with Domain Monitoring: Why It’s Essential for Your Business
An expired domain or a changed DNS record can take a business offline in an instant. What domain monitoring covers and how to set it up.
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Keeping Your Website Running Smoothly: A Guide to Tracking Server Status
A practical guide to server monitoring: which metrics to track, how to set useful alerts, how to read logs and how to fix the most common server problems.
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Prevent Missed Tasks: Ensure Your Cron Jobs are Running Smoothly
Backups, imports and cleanups run on cron, and they fail silently. Common causes of missed cron jobs, how to troubleshoot them and how to get alerted when a job does not run.
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Maximizing Your Website’s Potential with Reliable Uptime Monitoring
A website only earns when it is reachable. How reliable uptime monitoring protects revenue, what to look for in a service and how to act on the data.
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