Automatic host-side space management with SCSI thinly provisioned LUNs
If your host supports SCSI thin provisioning, you can enable the
space-allocation option in ONTAP to turn on automatic host-side space management.
Enabling SCSI thin provisioning enables you to do the following.
Automatic host-side space management
When data is deleted on a host that supports SCSI thin provisioning, host-side space management identifies the blocks of deleted data on the host file system and automatically issues one or more
SCSI UNMAPcommands to free corresponding blocks on the storage system.
Notify the host when a LUN runs out of space while keeping the LUN online
On hosts that do not support SCSI thin provisioning, when the volume containing LUN runs out of space and cannot automatically grow, ONTAP takes the LUN offline. However, on hosts that support SCSI thin provisioning, ONTAP does not take the LUN offline when it runs out of space. The LUN remains online in read-only mode and the host is notified that the LUN can no longer accept writes.