CDN Invalidation
Definition
CDN Invalidation is the process by which a caching system (in our case, a Content Delivery Network, or CDN) has content forcefully purged from its cache transparently, so updated content can be stored in the cache and sent back to clients for future requests.
If you make significant changes to the website (e.g., WordPress update, caching rule changes, etc.), you may want to invalidate the current CDN cache. The CDN will invalidate ALL objects currently in the cache, which means on next browser fetch by a client, they will be re-added to the CDN’s cache (based on the upstream server’s configured cache rules).
Default
By default, these are the CDN settings for caching:
| Field | Value | Notes |
|---|---|---|
| Minimum TTL | 1 second | - |
| Maximum TTL | 86400 second | - |
| Default TTL | 3600 second | If an object does not have cache headers, use this value |
| Cache Headers | Disabled | |
| Cache Query Strings | Enabled | |
| Cookies | Enabled | |
| Compression | Enabled | Supports both Gzip and Brotli |
In addition, these request paths will never be cached by the CDN:
/wp-login.php/wp-admin/*/wp-json/*/wp-cron.php/xmlrpc.php/wp-trackback.php/wp-signup.php