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Content Delivery Network

File updates and cache purging

Updated 4 min read

Invalidate old copies after replacing a file, distinguishing URL purges from directory purges.

Where to start and what to prepare

Go to CDN → Purge and prefetch. Available domains at the top lists usable domains. If none appear, use Bind domain or View domains to resolve setup and status.

Prepare complete resource URLs and confirm that the origin serves the new files. download.example.com below is a format example, not a domain you can submit for testing.

When to purge

If the origin replaces content at an unchanged URL while edge caches still hold the old version, submit a purge to invalidate those copies.

Purging does not upload files or clear files already cached in a visitor's browser. Check the new version at the origin before purging.

Choose a task type

Choose a task type
GoalUI optionInput
Update one file at the same URLURL purge → URLThe file's complete URL
Update multiple files in a directoryURL purge → DirectoryThe target directory URL; confirm the affected scope before submitting
Fetch files before a releaseURL prefetchComplete URLs of files to be released

Purge a file or directory

  1. Open Purge and prefetch and choose URL purge.
  2. Choose URL for one file. Choose Directory only when you intend to invalidate the entire directory.
  3. Enter one complete URL per line, including http:// or https://. Domains must belong to your account and be available for the operation. The current page accepts up to 100 entries per submission.
  4. Review the count and domains, then select Submit task.
  5. Check whether the task was accepted or submission failed, then visit the target file to verify its version.
Configuration example
https://download.example.com/releases/demo.zip

Example domains and paths are illustrative. Replace them with real resources you are authorized to use.

Accepted means the request was submitted successfully, not that every node has finished purging.

Why hit rates fall after a purge

After old cache entries expire, new requests must fetch from the origin, so hit rates may temporarily fall. Directory purges affect more files and usually have a larger impact than a single URL purge.

If a new release will receive many downloads, prefetch important files after purging. Use sensible versioned filenames instead of frequently purging entire directories.

Still seeing an old file after purging

  1. Check the origin directly to confirm the new file, path and size.
  2. Ensure the purged protocol, domain and path match the actual download URL.
  3. Check query-parameter rules and confirm that requests select the intended version.
  4. Rule out browser caches and old files in the download folder; compare checksums if needed.

Submit a prefetch task

  1. Choose URL prefetch and enter one complete file URL per line under Task paths.
  2. Review the URL count, deduplication and domains. The page accepts up to 100 entries per submission.
  3. Select Submit task, then check the operation type and status in Task records below.
  4. Verify access using a test file. Prefetching pulls content from the origin; it does not upload new files for you.

Interpret task status

Accepted means the platform received the request, not that all nodes are updated. Always verify the target file after a purge or prefetch.

Retry if task records cannot load. If submission fails, resolve the form or API error before resubmitting. Purging does not clear browser caches or replace files at the origin.