Working with Certificate Services
This is only applicable for backing up a server that has certificate services installed, e.g., Certificate Authority installed on Windows.
You can override the backup modes that jobs specify for backing up certificate services.
Force modes – Set the modes to use when a job specifies Full, Differential, and Incremental modes. For example, if you specify Full for the Incremental mode, Yosemite Server Backup runs a full backup even though a backup job specifies an incremental mode.