ComplianceClock is a secure time base that prevents compliant data from being tampered with. ComplianceClock makes it impossible to prematurely modify or delete data by altering system clock.
Starting with Data ONTAP 8.1, there are two types of ComplianceClock—volume ComplianceClock and system ComplianceClock. These two types of ComplianceClock minimize the ComplianceClock lag and enable the expiry of WORM files with extended retention.
