Honor No-Cache Request

Applies To:

HTTP LargeThis platform has been optimized to cache and deliver static content (e.g., HTML, CSS, JavaScript, ISO, multimedia, and software downloads, etc.) over HTTP or HTTPS.

HTTP SmallLegacy. If you are currently serving traffic over this platform, then you may continue to do so. However, we recommend that you serve your traffic over our more robust HTTP Large platform.

ADNThe Application Delivery Network platform has been optimized to deliver dynamic content (e.g., login credentials, account information, etc.) over HTTP or HTTPS. Typically, user-specific and database-driven content are served over this platform.

Rules EngineAllows the customization of how requests are handled by our CDN service. It may be used to override the default response provided by an origin server, CDN settings, and the default edge server behavior. - Basic

Category: Caching

Purpose: Determines whether a client's no-cache request will be forwarded to the origin server.

A no-cache request occurs when the HTTP client sends a Cache-Control:no-cache and/or Pragma:no-cache header in the HTTP request.

Enabled	Result
Yes	Allows an HTTP client's no-cache requests to be forwarded to the origin server, and the origin server will return the response headers and the body through the edge server back to the HTTP client.
No	Restores the default behavior. The default behavior is to prevent no-cache requests from being forwarded to the origin server.

For all production traffic, it is highly recommended to leave this feature in its default disabled state. Otherwise, origin servers will not be shielded from end-users who may inadvertently trigger many no-cache requests when refreshing web pages, or from the many popular media players that are coded to send a no-cache header with every video request. Nevertheless, this feature can be useful to apply to certain non-production staging or testing directories, in order to allow fresh content to be pulled on-demand from the origin server.

The cache status that will be reported for a request that is allowed to be forwarded to an origin server due to this feature is TCP_Client_Refresh_Miss. The Cache Statuses report, which is available in the Core Reports module, provides statistical information by cache status. This allows you to track the number and percentage of requests that are being forwarded to an origin server due to this feature.

Default Behavior: Disabled.