The Belle II Online–Offline Data Operations System

Data collection at the Belle II experiment started in the spring of 2019. During the early stages of the experiment it is important that the raw data are both copied to permanent storage and made available soon after being recorded to allow for the timely commissioning and calibration of the detector. Automated procedures have been developed to transfer the data from the detector in a timely manner; these procedures include fault management, performance monitoring, and quality checks. It is important that the systems put in place will also scale to the much higher data rates expected in the coming years at Belle II. The development, implementation, and operations of the Belle II online–offline data transfer system will be described.