Overview: A Web server automatically redirects to the 404 Not Found page when returning an HTTP 404 status code. A URL becomes inaccessible when the webpage URL generation rules are changed, webpage files are renamed or moved, and the entered inbound link has a spelling mistake. When the Web server receives a request from a browser for accessing this URL, it returns a 404 status code, notifying the browser that the requested resource does not exist.
This error is due to the following three causes:
1. The website cannot be accessed through the request port.
2. The request is blocked by the Web service extensions locking policy.
3. The request is blocked by the MIME mapping policy.
Note: During access to a single resource, if a 404 status code is returned because of a resource finding failure, the 404 Not Found page is displayed. If the accessed URL contains multiple resources and only a portion cannot be accessed normally, the 404 Not Found page will not be displayed
Function description: On the Alibaba Cloud CDN Console, the “Customize the 404 Page” option is provided in the basic configuration of “Add Domain Name” or “Manage”. You can select a proper 404 page based on your service needs
1. By default, 404 page customization is disabled. The 404 Not Found page is displayed by default
2. When “Default 404 Page” is selected and an HTTP 404 status code is returned, the default 404 Not Found page is displayed
3. When “User-Defined 404 Page” is selected, you need to design and edit the 404 page consistent with your website’s overall style, and save the page resources to the origin site domain like other static files. The page resources are accessible by entering the complete Alibaba Cloud CDN domain URL (including http://)