Deploying an SAP HANA multinode scale-out cluster on FC-connected systems requires the SAP HANA storage connector (fcClient). The storage connector is responsible for mounting and unmounting the persistence (data and log) to the SAP HANA worker nodes.
The storage connector also writes SCSI-3 persistent reservations (PRs) to the devices. The Linux sg_persist command initiates an operation known as I/O fencing, which ensures that only one SAP HANA worker host has simultaneous access to a set of data and log devices.