Website Downtime Checklist: What to Check First
When your site goes dark, minutes matter. Follow this ordered checklist to find the cause fast: DNS, hosting, SSL, CDN and application layers.
Outages feel chaotic because every layer of the stack can be the culprit. This checklist orders the checks from the fastest to rule out to the deepest — so you stop guessing and start fixing within minutes instead of hours.
1. Confirm it is actually down
Before you wake the team, verify from more than one network. Continuous uptime monitoring with response-status checks — like PatchPings — helps separate a real outage from a local ISP or VPN glitch. If only you cannot reach the site, flush DNS or try a mobile connection off Wi-Fi.
2. DNS and domain
- Check whether the domain resolves — expired registration is an instant full outage.
- Verify nameservers match what you expect; a stale NS change can point traffic nowhere.
- Look for recent DNS record edits that pointed the apex or
wwwat the wrong target.
3. SSL and certificates
An expired or mis-issued certificate shows as a hard browser block even when the server is running. Check expiry dates, whether the served hostname matches the certificate, and whether auto-renewal failed silently. Our SSL expiry guide covers the two-layer defence that prevents this class of outage.
4. Hosting and CDN
- Check your hosting provider status page — regional failures happen before your app does anything wrong.
- Purge or bypass the CDN temporarily to see if the origin responds directly.
- Review recent deploys; a bad release is the most common application-layer cause.
5. Application and database
If infrastructure is healthy, SSH or open your platform logs. Look for 502/503 from the reverse proxy, database connection errors, and disk-full conditions. Roll back the last deploy if errors started at a known timestamp.
Note start time, what failed, and what fixed it. Post-incident reviews only work when the timeline is accurate.
After recovery
- 1Send a recovery notification so stakeholders know the site is back.
- 2Add or tune monitoring so the next failure pages you before customers notice.
- 3Schedule a short retrospective — recurring outages at the same hour often trace to cron jobs or traffic spikes.
The teams that recover fastest are not luckier — they have a checklist, external monitors, and alerts they trust. Download PatchPings for uptime checks and SSL watch, so the next outage finds you first.
