You can enable data compression only on FlexVol volumes that are contained within 64-bit aggregates. You can enable data compression to achieve space savings by using the sis config command.
You can enable both inline and postprocess compression or only postprocess compression on a volume. Before enabling inline compression, you must enable postprocess compression on the volume.
The following command enables postprocess compression on the volume VolA: sis config -C true /vol/VolA
The following command enables both postprocess and inline compression on the volume VolA:sis config -C true -I true /vol/VolA