|Default value||The null string; Automatic Storage Management discovery finds all disks in an operating system-specific location to which the Automatic Storage Management instance has read/write access.|
|Oracle RAC||Multiple instances can have different values. Different nodes might see the same disks under different names; however, each instance must be able to use its
Note:This parameter may only be specified in an Automatic Storage Management instance.
ASM_DISKSTRING specifies an operating system-dependent value used by Automatic Storage Management to limit the set of disks considered for discovery. When a new disk is added to a disk group, each Automatic Storage Management instance that has the disk group mounted must be able to discover the new disk using the value of
In most cases, the default value will be sufficient. Using a more restrictive value may reduce the time required for Automatic Storage Management to perform discovery, and thus improve disk group mount time or the time for adding a disk to a disk group. A "?" at the beginning of the string gets expanded to the Oracle home directory. Depending on the operating system, wildcard characters can be used. It may be necessary to dynamically change
ASM_DISKSTRING before adding a disk so that the new disk will be discovered.
An attempt to dynamically modify
ASM_DISKSTRING will be rejected and the old value retained if the new value cannot be used to discover a disk that is in a disk group that is already mounted.