1. Always Online™ cache is built from Cloudflare’s Always Online™ crawler. It crawls Free customers once every 7 days, Plus and Pro customers once every 3 days, with Premium customers crawled daily. Note: The crawler does not obey robots.txt.
  2. Only content hosted on the domain that has Always Online™ enabled will be cached in the Always Online™ cache.
  3. Cloudflare doesn’t cache every page on your site. A limited cache of your site will be displayed,  generally 1-3 pages, which means that only some pages on your site will be viewable if your server goes down.
  4. Recently added sites won’t have a large cache of pages available, which means that Always Online™ may not work if you very recently added the site.
  5. Cloudflare won’t be able to show private content or handle form submission (POST, SSL) if your server is down. An error will be displayed on checkout pages or pages requiring a login to view.
  6. In order to trigger Always Online™, your web server must be returning a standard HTTP timeout Error code of 502 or 504. Always Online™ will also work when it encounters issues contacting your server (Cloudflare Errors 521 & 523), timeouts (522 & 524), SSL errors (525 & 526) or an unknown error (520). Always Online™ will not be triggered for other HTTP response codes, such as 500, 503, database connection errors, internal server errors, or empty replies from the server.
  7. If you are on a paid Cloudflare plan, we recommend customizing the Cloudflare error pages that may be displayed when Always Online™ is triggered.
  8. If your site has a database error (database connection or otherwise) Always Online™ will not be triggered, as your web server is likely still available even if there are database issues.
  9. Having caching headers coming from your server in the response (Cache-Control, Expires, etc.) that tell us not to cache the resource will cancel out most of Cloudflare’s caching ability and Always Online™.
  10. If you have the United States listed as a country on your Threat Control block list, the Always Online™ crawler will not be able to crawl your site.
  11. A “Cache Everything” page rule is enabled with the “Edge Cache Expire TTL” lower than the caching frequency (Free customers: 7 days, Pro customers: 3 days, and Business and Enterprise customers: 1 day). In this cache, the Edge Cache Expire TTL will cause the Always Online™ cache to be purged in the corresponding interval.