Configure the refresh and prefetch features

Alibaba Cloud Content Delivery Network (CDN) allows you to refresh and prefetch resources. You can use the refresh feature to force the CDN nodes to retrieve the latest resources from the origin servers. You can use the prefetch feature to fetch frequently requested resources during off-peak hours. This accelerates content delivery. This topic describes how to configure the refresh and prefetch features and how to query the refresh and prefetch records.

1. Log on to the Alibaba Cloud CDN console.
2. In the left-side navigation pane, click Refresh & Prefetch.
3. On the Refresh and Prefetch page, click the Refresh Cache tab and set the following parameters to refresh or prefetch resources based on your business requirements.
   

   Parameter	Description
   Operation	The operation that you want to perform. Supported options: Refresh After resources are updated on the origin server, you can refresh the URLs of the resources. The system then automatically clears the data of the resources that are cached on the CDN nodes. When clients visit the refreshed URLs, the corresponding CDN nodes redirect the requests to the origin server. Alibaba Cloud CDN then retrieves the latest resources from the origin server and returns them to the clients. The retrieved resources are also cached on the CDN nodes. Prefetch You can prefetch frequently requested resources or less frequently visited accelerated domain names during off-peak hours to increase the cache hit ratio.
   Object	The type of the object that you want to refresh or prefetch. Available options: Directory This option is available only when you set Operation Type to Refresh. URL This option is available when you set Operation Type to Refresh or Prefetch.
   URL	If you need to refresh or prefetch multiple URLs, enter one URL on each line. When you enter URLs, note that: Refresh resources based on directories Each URL must start with the string http:// or https://, and end with a forward slash (/). You can refresh up to 100 directories with each Alibaba Cloud account per day. A maximum of 100 directories can be submitted at a time. Refresh resources based on URLs Each URL must start with the string http:// or https://. You can refresh up to 2,000 URLs with each Alibaba Cloud account per day. A maximum of 1,000 URLs can be submitted at a time. Prefetch resources based on URLs Each URL must start with the string http:// or https://. You can prefetch up to 500 URLs with each Alibaba Cloud account per day. A maximum of 100 URLs can be submitted at a time.

4. Click Submit.
5. Click the Records tab.
6. On the Records tab, specify a time range and an operation type, enter a domain name or a URL, and then click Search.

   You can check the refresh and prefetch records, including the refreshed or prefetched object, type, time, status, and progress of each operation.