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Uptime issues

Uptime troubleshooting ​

These pages explain each uptime failure that turns a site Down or Needs attention, and how to fix it.

If you're not sure which failure you have, start with the site is down page. It matches what you see in the browser to the specific failure causing it.

Connection issues ​

The request never reaches your server.

  • Connection refused — the server rejected the connection. Usually a stopped web server, firewall rule, or the server binding to localhost only.
  • Connection timeout — nothing replied within the timeout window. Usually server overload, a deadlocked process, or a network black hole.
  • DNS resolution failed — the domain couldn't be resolved to an IP address. Could be an expired domain, missing records, or a nameserver problem.

HTTP response issues ​

The server responds, but with an error code instead of your page.

  • HTTP 4xx response — the server rejected the request. Common causes are authentication requirements on the checked URL, WAF rules, or a moved page.
  • HTTP 5xx response — the server returned an error. Covers 500 application crashes, 502/504 upstream failures, and 503 service unavailable.

Performance issues ​

The site loads, but slowly enough that your visitors notice.

  • Site responding slowly — the site responds, but too slowly, so DomainDash marks it Needs attention. Shows you how to find the bottleneck, whether it's DNS, the server, or content delivery.

Catch this automatically

DomainDash keeps an eye on this for you — and tells you in plain English the moment something needs your attention, before your visitors notice. Set up in under a minute, no credit card.

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Last updated: 13 October 2026