You can set the period of caching your content on CDN servers in the Control Panel. After the cache expiration time is over CDN servers send a request to the origin again.
CDN servers might determine that the file on the origin has not been changed. Then they will return to the end-users the same file for another Cache Expiry period. If the file on the origin has been changed CDN servers will cache the new file.
You can use the cache parameters from the origin or set up the new values in your account.
CDN Caching option has two types of working:
- Origin controlled
- CDN controlled
Use this option if there is no Cache-Control header on your Origin or if you need to set up another cache period for CDN. 4xx and 5xx code won't be cached be the default.
You could add a custom cache period for specific HTTP codes by the Advanced Caching Rule option.
Content will be cached due to Cache-Control headers from your origin. If your origin doesn't have Cache-Control headers, the content will be cached on the servers for the period specified in the Default Cache Expire option.
The Default Cache Expire option will apply only for 200, 201, 204, 206, 301, 302, 303, 304, 307, 308 HTTP response codes.
Note! If the content is not requested by end-users it will be removed from the cache after 36 hours.