ORACLE 参数之 ASM_DISGROUPS

ASM_DISKGROUPS

Property Description

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

Note:

This parameter may only be specified in an Automatic Storage Management instance.

ASM_DISKGROUPSspecifies a list of names of disk groups to be mounted by an Automatic Storage Management instance at instance startup. Oracle ignores the value that you set forASM_DISKGROUPSwhen you specify theNOMOUNToption at startup or when aALTER DISKGROUP ALL MOUNTstatement is issued.

Automatic Storage Management (ASM) automatically adds a disk group to this parameter when the disk group is successfully created or mounted, and automatically removes a disk group from this parameter when the disk group is dropped or dismounted.

Issuing theALTER DISKGROUP...ALL MOUNTorALTER DISKGROUP...ALL DISMOUNTcommand does not affect the value of this parameter.

该变量只是在ASM实例中被设置；

ASM_DISGROUPS 参数列出了ASM实例在启动的时候MOUNT的磁盘组列表，如果在启动时，手动指定了NOMOUNT选项或者执行ALTER DISKGROUP ALL MOUNT语句时，该参数被忽略； 在你成功创建一个磁盘组或MOUNT一个磁盘组时，ASM自动维护到该变量列表；反之，如果磁盘组被DROP或DISMOUNT，那么自动会在列表中去除该磁盘组名称；

OCP 考核题库：

Q129. Which initialization parameter in an ASM instancespecifies the disk groups to be automatically mounted at instance startup?

A.ASM_DISKMOUNT

B.ASM_DISKGROUPS

C.ASM_DISKSTRING

D.ASM_MOUNTGROUP

Answer: B

相关参考：

http://docs.oracle.com/cd/E11882_01/server.112/e18951/asminst.htm#OSTMG10141