Oh Dear says my site is down, but it's working for me. What's going on?
Nine times out of ten, a WAF, bot-protection service, or firewall is silently blocking Oh Dear's checks. Your visitors load the site fine, but our monitoring requests get a 403, a challenge, or a connection reset, and we report it as down.
Here's a quick troubleshooting flow for this and the other common causes.
1. A WAF, firewall, or bot-protection service is blocking Oh Dear
Services like Cloudflare, Akamai, Fastly, Sucuri, and custom WAFs sometimes block our checks even though real humans load the site just fine.
- Check your WAF / firewall logs for requests from our IP ranges.
- Whitelist our IPs and User-Agent. For Cloudflare specifically, see How to whitelist Oh Dear static IPs or User Agent in Cloudflare.
This is by far the most common cause of phantom "site is down" alerts.
2. Your origin is down but the CDN is serving a cached page
The opposite of the previous case. You browse to the site, the CDN hands you a cached response, and everything looks fine. Meanwhile, Oh Dear's check is either bypassing the cache or requesting a path the CDN can't cache, and hits your actually-down origin.
See How can I monitor the origin server? for the right way to monitor both layers.
3. Geographic routing differences
Some sites serve different content or behave differently depending on where the request comes from. Our checkers run from a handful of regions (see Can I choose where Oh Dear checks my site from?). If you're browsing from a different region, you may genuinely see different results.
Try visiting your site through a VPN endpoint near our checker region to see the experience from our angle.
4. The site was briefly down
Our uptime checks run every minute, from multiple regions, with cross-verification before we fire an alert. We're pretty confident about what we report. If a check fails and the secondary region also fails, the site was genuinely unreachable from the public internet for that window, even if it came back quickly.
Check the monitor's incident log for the exact timestamp and duration. Often a 1-minute blip turns out to be a deploy, a brief DNS hiccup, or a backend restart.
5. DNS / SSL issues
A DNS misconfiguration or an invalid certificate can make the site reachable from machines with cached entries while failing for fresh lookups. Our checkers always do a fresh lookup. Use a tool like whatsmydns.net or dig @1.1.1.1 yoursite.com to verify your DNS from outside your own network.
Still stuck?
If none of the above match, contact support with the monitor URL and the approximate time of the incident. We can pull the raw check logs, including the exact response we got, and walk through it with you.
