Space Guarantee

A space guarantee controls how storage for the FlexClone is managed in relation to its containing aggregate. By default, a FlexClone inherits the space guarantee of its parent volume, but you can select a different guarantee type. There are three possible settings:

• volume—Data ONTAP pre-allocates space in the aggregate for the FlexClone. The pre-allocated space cannot be allocated to any other volume or FlexClone in that aggregate.

  Space management for a FlexClone with space guarantee of volume is equivalent to that of a traditional volume or to all volumes in versions of Data ONTAP earlier than 7.0.

• file—Data ONTAP pre-allocates space in the FlexClone so that any file in the FlexClone with space reservation enabled can be completely rewritten, even if its blocks are pinned for a snapshot.

• none—Data ONTAP reserves no extra space for the FlexClone. Writes to LUNs or files contained by that FlexClone could fail if the containing aggregate does not have enough available space to accommodate the write.

Note: Because out-of-space errors are unexpected in a CIFS environment, do not set the space guarantee to none for FlexClone volumes accessed using CIFS.

Space guarantees are honored only for online volumes. If you take a FlexClone volume offline, any committed but unused space for that FlexClone becomes available for other volumes in that aggregate. When you bring that FlexClone back online, if there is not enough available space in the aggregate to fulfill its space guarantees, you must use the force (-f) option to disable the space guarantees of the FlexClone in order to bring it back online.

You can also use the space guarantee setting to pursue an aggregate overcommitment strategy.

For more information about space management issues, see the Data ONTAP Storage Management Guide.