"There was an error. The backup storage is currently not available" after cloud cache reconfiguration

Removed the existing cache drive in favor of multiple smaller cache drives. Now, when accessing the WebUI I get “There was an error. The backup storage is currently not available”. I see the new drive is ready to be initialized but get an error when trying to format it. Logs were uploaded and assigned case id 180.

For the record: This was an issue with the old Amazon Web Services appliance image (automatic cache formatting doesn’t work there when updated).