The CacheDrive allows you to access a practically unlimited amount of storage by keeping all of your files in the cloud and caching frequently used files for fast local access. When copying a large folder to the CacheDrive, however, access to the unlimited cloud storage happens at Internet speeds which are usually orders of magnitude slower than the LAN.
Because of the large discrepancy between LAN and WAN speeds, the cache may fill up before it can upload all files to permanent cloud storage, especially if multiple users are copying to the CacheDrive at the same time. To prevent this from happening, you may see an error message if you try to copy a folder that is larger than the writable cache space.
To work around this issue, we suggest copying smaller-than-writable-cache sized chunks of data and allowing the CacheDrive to upload to the cloud before copying the next chunk. The CacheDrive will then be able to cache-out files to make space for the next set of files.
To determine the writable size of the cache, login to MCM and see the Devices page. Expand the section for the device and you will see the writable size.