How volumes work

Volumes contain file systems that hold user data that is accessible via one or more of the access protocols supported by Data ONTAP, including NFS, CIFS, HTTP, WebDAV, FTP, FCP, and iSCSI.

Each volume depends on its containing aggregate for all its physical storage, that is, for all storage in the aggregate’s disks and RAID groups.

• A comparison of FlexVol volumes and traditional volumes
  A volume is associated with its containing aggregate differently, depending on whether it is a FlexVol volume or a traditional volume.
• Limits on how many volumes and aggregates you can have
  The limits on how many volumes and aggregates you can have depends on your storage system model and your Data ONTAP version.
• Attributes you can set for volumes
  Volumes have a set of attributes that determine how they can be used.
• How volumes use the language attribute
  Every volume has a language. The language of the volume determines the character set Data ONTAP uses to display file names and data for that volume.
• How you manage duplicate volume names
  Data ONTAP does not support having more than one volume with the same name on a storage system. Data ONTAP renames such volumes, but the name it uses can cause problems, so you need to take corrective action.
• Volume states and status
  Volumes can be in one of three states—online, offline, or restricted. In addition, they can show one or more status values, depending on how they are configured and the health of their disks.
• About the CIFS oplocks setting
  Usually, you should leave CIFS oplocks on for all volumes and qtrees. This is the default setting. However, you might turn CIFS oplocks off under certain circumstances.
• How security styles affect access to your data
  Every qtree and volume has a security style setting—NTFS, UNIX, or mixed. The setting determines whether files use Windows NT or UNIX (NFS) security. How you set up security styles depends on what protocols are licensed on your storage system.
• How Data ONTAP can automatically provide more free space for full volumes
  Data ONTAP can automatically make more free space available for a FlexVol volume when that volume is nearly full. You can choose to make the space available by first allowing the volume size to increase, or by first deleting Snapshot copies.