V$ASM_DISKGROUP

In an Automatic Storage Management instance, V$ASM_DISKGROUP displays one row for every disk group discovered by the Automatic Storage Management instance. In a database instance, V$ASM_DISKGROUP displays one row for every Automatic Storage Management disk group mounted by the local Automatic Storage Management instance.

Column	Datatype	Description
`GROUP_NUMBER`	`NUMBER`	Cluster-wide number assigned to the disk group (primary key)
`NAME`	`VARCHAR2(30)`	Name of the disk group
`SECTOR_SIZE`	`NUMBER`	Physical block size (in bytes)
`BLOCK_SIZE`	`NUMBER`	Automatic Storage Management metadata block size (in bytes)
`ALLOCATION_UNIT_SIZE`	`NUMBER`	Size of the allocation unit (in bytes)
`STATE`	`VARCHAR2(11)`	State of the disk group relative to the instance: `CONNECTED` - Disk group is in use by the database instance `BROKEN` - Database instance lost connectivity to the Automatic Storage Management instance that mounted the disk group `UNKNOWN` - Automatic Storage Management instance has never attempted to mount the disk group `DISMOUNTED` - Disk group was cleanly dismounted by the Automatic Storage Management instance following a successful mount `MOUNTED` - Instance is successfully serving the disk group to its database clients
`TYPE`	`VARCHAR2(6)`	Redundancy type for the disk group: `EXTERN` `NORMAL` `HIGH`
`TOTAL_MB`	`NUMBER`	Total capacity of the disk group (in megabytes)
`FREE_MB`	`NUMBER`	Unused capacity of the disk group (in megabytes)

Note:

The GROUP_NUMBER, TOTAL_MB, and FREE_MB columns are only meaningful if the disk group is mounted by the instance. Otherwise, their values will be 0.