I was troubleshooting a weird issue with Cisco Unity Connection 10.5(1): after the upgrade from version 9.1 the backups started to fail. The message was: “ERROR: Backup failed due to an interruption during file copy to backup media, Backup Completed…” What was odd about this issue is that the actual files were written to the SFTP server just fine and all backup jobs showed successful results for individual components that have been backed up:
The fix? Remove older (9.x) CUC backup files from your SFTP server and try backup up CUC again.