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:Differences between Alibaba Cloud Content Delivery Network configuration back-to-origin HOST and origin

Last Updated:Jan 12, 2022


When you use the Alibaba Cloud Content Delivery Network console to add domain names, you often confuse the concepts of origin and back-to-origin HOST. This paper gives examples of these two concepts.


Differences between an origin server and an origin host:

  • An origin server defines a specific IP address to which back-to-origin requests are redirected.
  • Back-to-origin host: The origin host determines the site to which the back-to-origin request accesses the IP address.
    Back-to-origin HOST is the back-to-origin domain name. When multiple Domain service are provided on the origin server, the specific site domain name that is accessed on the origin server when the Alibaba Cloud Content Delivery Network node is back-to-origin.

Example 1: The origin site is a domain name

If the origin server is, the back-to-origin host is set to Then the actual back-to-origin is the site on the corresponding host of the IP address to which the is resolved.

Example 2: The origin is an IP address

The origin server is, and the back-to-origin host is Then the actual return is site on the corresponding host.

Applicable scope

  • CDN