The Sun JDK zip API fails when trying to open zip files larger than 2 GB. It has been suggested that we should investigate alternative APIs.
14:31:58,158 ERROR [ExportUtils] Error determining export type from export zip: /data/confluence/restore/david.zip
java.util.zip.ZipException: invalid END header (bad central directory size)
at java.util.zip.ZipFile.open(Native Method)
In the meantime, the suggested workaround for this issue is to disable automatic backups and backup the Confluence database and home directory using an external scheduling system.