How thin provisioning works in netapp dataontap

The NetApp Data ONTAP operating environment combines physical disks into RAID groups that consist of data disks and parity disks. RAID groups are collected in a storage pool called an aggregate. An aggregate is a collection of RAID groups.

FlexVol® volumes are created within aggregates. FlexVol volumes are the logical containers that store data. Hosts using NAS protocols access and store data directly in FlexVol volumes. For SAN environments, LUNs are created inside FlexVol volumes and hosts access the LUNs. FlexVol volumes are not directly associated with particular underlying disks in the aggregate. This abstracts logical data storage containers from underlying physical storage containers, providing the flexibility that makes thin provisioning and other NetApp storage features possible.

 FlexVol volumes allow you to use soft allocation to thin provision more space than is available in the physical aggregate.

Data ONTAP implements thin provisioning at the FlexVol volume and LUN level. In SAN environments, you can create thinly provisioned LUNs inside thinly provisioned FlexVol volumes. A simple storage option determines whether a particular volume or LUN is guaranteed physical space from the disk aggregate. This means that if you aren’t currently using thin provisioning, you can enable it—on your existing volumes and LUNs—simply by changing a single option and without disrupting ongoing operation