ASM_DISKGROUPS

2.18 ASM_DISKGROUPS

ASM_DISKGROUPS specifies a list of disk group names that an Oracle ASM instance mounts at startup when the ALTER DISKGROUP ALL MOUNT statement is issued.

Property	Description
Parameter type	String
Syntax	`ASM_DISKGROUPS =` `diskgroup` `[,` `diskgroup` `] ...`
Default value	There is no default value.
Modifiable	`ALTER SYSTEM`
Modifiable in a PDB	No
Range of values	Comma-separated list of strings, up to 30 characters
Basic	No
Oracle RAC	Multiple instances can have different values.

Note:

This parameter may only be specified in an Oracle Automatic Storage Management (Oracle ASM) instance.

The Oracle ASM instance startup process executes ALTER DISKGROUP ALL MOUNT unless the NOMOUNT startup option is specified.

The ASM_DISKGROUPS parameter is dynamic. If you are using a server parameter file (SPFILE), then you do not have to manually alter the value of ASM_DISKGROUPS in most situations. Oracle ASM automatically adds a disk group to the parameter when the disk group is successfully created or mounted. Oracle ASM also automatically removes a disk group from the parameter when the disk group is dropped. However, the SPFILE is not updated on a manual dismount.

Issuing the ALTER DISKGROUP...ALL MOUNT or ALTER DISKGROUP...ALL DISMOUNT command does not affect the value of this parameter.

Supporting Up to 511 Disk Groups for an Oracle ASM Instance

In Oracle Database 12c Release 1 or later, Oracle ASM configurations support up to 511 disk groups. Oracle ASM configurations with Oracle Database releases before 12c Release 1 can only support up to 63 disk groups.