I changed a thumbnail, but it's not updating in the collection view

This is due to caching, which happens at several levels:

• Cloudflare, which sits between users and Arca
• Drupal's cache
• Islandora Imagecache, which caches thumbnails in particular (to avoid having each view request hit the Fedora server)
• Your browser

The first three affect all users looking at your repository. The last is only visible to you -- if other people report seeing the updated thumbnail but you only see the old version, then it's your own browser caching the image, and not a problem - just clear your cache.

Cloudflare's cache is automatically purged at regular intervals. The Drupal cache and Islandora Imagecache do the same, but might occasionally need some manual nudging. Your browser's cache can only be cleared by you. In general, if you update a thumbnail and you don't see the new version appear right away, it's usually just a matter of waiting for the caches to update themselves.

To confirm that your thumbnail update went through: Manage your object, go to Datastreams, and look at the TN datastream. Click the TN link, and you should see the most recent version of the thumbnail. You can also click the number in the Versions column, to review the current and previous versions.

If your thumbnails aren't updating after a long wait: Clear the caches manually.

• Clear the Drupal cache: In the Admin toolbar, Under the Home button, click Flush All Caches.
• Clear Islandora Imagecache: In the Admin toolbar, go to Configuration -> Media -> Imagecache External -> Flush External Images.
• Clear the Image Styles: Under the Home icon in the Admin toolbar, choose Flush All Image Styles.
  • If this is not available, enable the module (at admin/modules) Image Style Flush, and grant the permission "Flush image styles" to the Local Adminstrator.

After doing this, you may need to clear your own browser's cache before the updated thumbnails will be visible to you.