Learn uptime monitoring
Clear, practical explanations of the concepts behind reliable websites and services — from what “99.9% uptime” really allows to writing incident updates customers trust.
What Is Uptime Monitoring? A Complete Explainer
Uptime monitoring checks your website, API or server on a schedule and alerts you when it fails. Learn how it works, check types, intervals and what to monitor.
Uptime Percentages Explained: The Nines and Allowed Downtime
What 99%, 99.9%, 99.99% and 99.999% uptime really allow in downtime per day, week, month and year, with exact figures, conventions and how to pick a target.
How to Monitor Website Uptime: A Step-by-Step Guide
A step-by-step guide to monitoring website uptime: which pages and endpoints to check, intervals, keywords, SSL, DNS, domain expiry and alert routing.
How to Monitor Cron Jobs with Heartbeats (Dead Man's Switch)
Learn how to monitor cron jobs with heartbeat (dead man's switch) checks: curl in crontab, && chaining, systemd timers, Kubernetes CronJobs and grace periods.
What Is a Status Page? Purpose, Contents and Best Practices
A status page shows live service health and incident updates. Learn why you need one, what to include, public vs private pages and how to write updates.
Incident Communication Templates for Status Pages and Postmortems
Incident communication templates for each stage: investigating, identified, monitoring and resolved, plus maintenance notices and a postmortem outline.
How to Reduce False Positive Uptime Alerts
False alerts cause alert fatigue. Learn how failure confirmation, timeouts, keyword checks, maintenance windows, dependencies and routing cut alert noise.
SLA vs SLO vs SLI: Definitions, Error Budgets and Examples
SLA, SLO and SLI explained in plain English: how they differ, how to calculate an error budget with a worked example, and how to measure reliability.
SSL Certificate Expiry: Why Certificates Expire and How to Monitor Them
Why SSL/TLS certificates expire, how shorter lifetimes affect you, how to check expiry dates with openssl, and a checklist to avoid certificate-related outages.
How to Calculate the Cost of Website Downtime
Estimate what website downtime costs your business with a simple formula covering lost revenue, staff time, SLA credits and recovery, plus a worked example.
How to Choose an Uptime Monitoring Tool: A Buyer's Checklist
Buyer's checklist for uptime monitoring tools: check intervals, confirmation, alert channels, status pages, seats, history, pricing and self-hosted vs SaaS.
How to Monitor API Endpoints: Health Checks, Assertions and Workflows
How to monitor REST API endpoints: design a good /health endpoint, add status and JSON assertions, handle authentication safely and chain multi-step API checks.
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