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Monitoring
guides.
Everything you need to know about uptime monitoring, from getting started to advanced reliability practices. Free, practical, actionable.
How to Monitor Website Uptime
A comprehensive guide covering what uptime monitoring is, why it matters, the different types of checks, and how to set up your first monitor with best practices for alerts and status pages.
Read guideWebsite Downtime Cost Calculator
Calculate how much downtime is costing your business. Enter your revenue and team details to see per-minute costs and compare uptime tiers from 99% to 99.99%.
Read guideWebsite down? A step-by-step checklist to find the cause
Work through a down website in order: is it only you, DNS, TLS, network, HTTP, the server, deploys, the database and third parties. With exact commands.
Read guideCron job monitoring: how to know when a job fails
Cron jobs fail without telling anyone. Learn the heartbeat pattern, how to set an interval and grace period, and copy examples for crontab and systemd.
Read guideSSL certificate expiry: check, monitor and renew
Check when an SSL certificate expires with openssl, see why auto-renewal fails, set alert thresholds, and follow a runbook to renew in time.
Read guideDNS records explained: A, AAAA, CNAME, MX, TXT and more
What each DNS record does, with zone file examples and the common mistake for each: A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV, PTR, SPF, DKIM, DMARC.
Read guideHTTP status codes explained: what each means for uptime
What every common HTTP status code means, who sends it, and which ones mean your site is down. Covers 502 vs 503 vs 504, Cloudflare 52x and curl.
Read guideUptime and SLAs explained: what 99.9% really allows
How uptime is calculated, how much downtime 99.9% or 99.99% allows, SLA vs SLO vs SLI, check intervals, compound availability and error budgets.
Read guideHow to write an incident postmortem (with a template)
How to write a blameless incident postmortem: the sections, one worked example, the five whys, action items with owners, and a template to copy.
Read guideStatus pages: what to put on one and how to write updates
What belongs on a status page, how to split a product into components, which states to use, and how to write incident updates, with worked examples.
Read guideOn-call rotations: how to set one up people can live with
How to set up an on-call rotation: rota shapes, escalation steps with exact minutes, what should page a person, handovers, runbooks and fair load.
Read guideAPI monitoring: what to check and how to set it up
What to monitor on an API: availability, correctness, latency, certificate and DNS. With /health examples in Express and FastAPI and curl tests.
Read guideMore topics
we cover.
SSL Monitoring
Track certificate expiry and chain issues
Status Pages
Communicate incidents to your users
API Monitoring
Validate endpoints and response times
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