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Error 523

Error 523: origin is unreachable

This error occurs when Cloudflare cannot contact your origin web server.

Common causes

This typically occurs when a network device between Cloudflare and the origin web server does not have a route to the origin's IP address.

Resolution

Contact your hosting provider and share the necessary error details to exclude the following common causes at your origin web server:

  • Confirm the correct origin IP address is listed for A or AAAA records within your Cloudflare DNS app.
  • Troubleshoot Internet routing issues between your origin and Cloudflare, or with the origin itself.

If none of the above leads to a resolution, request the following information from your hosting provider or site administrator:

  • An MTR or traceroute from your origin web server to a Cloudflare IP address that most commonly connected to your origin web server before the issue occurred. Identify a connecting Cloudflare IP from the logs of the origin web server.