NetApp
Storage > Volumes : Understanding volumes : How to manage the root volume

How to manage the root volume
The storage system's root volume contains special directories and configuration files that help you administer the storage system.
The root volume is installed at the factory on FAS systems and on V-Series systems ordered with disk shelves.
Note: For a V-Series system that does not have a disk shelf, you install the root volume on the third-party storage. If you use a FlexVol volume for the root volume, you must ensure that it has a space guarantee of volume. For more information, see the Data ONTAP 7-ModeSoftware Setup Guide.
Unless the installer selected a unique volume name during setup, the default root volume name, /vol/vol0, is used.
You can designate a different volume to be the new root volume. Starting in Data ONTAP 8.0.1, you can use a 64-bit volume for the root volume.
The root aggregate contains the root volume. Starting with Data ONTAP 8.1, newly created aggregates are 64-bit by default, and new systems are shipped with the root volume in a 64-bit aggregate. You should not include other volumes in the root aggregate.
By default, the storage system is set up to use a hard disk drive (HDD) aggregate for the root aggregate. When no HDDs are available, the system is set up to use a solid-state drive (SSD) aggregate for the root aggregate. If you want to change the root aggregate, you can choose either an HDD aggregate or an SSD aggregate to be the root aggregate (by using aggr options aggr_name root), provided that the corresponding type of disk drives are available on the system.
For more information about traditional and FlexVol volumes, see the Data ONTAP 7-ModeStorage Management Guide .