Automatic Storage Management (hereafter ASM) can be used for 1:1 standby operation or scalable operation only, but not for mutual standby operation and N:1 standby operation.
1:1 standby operation
Create an ASM instance resource.
The ASM instance will not be monitored, but only started or stopped
If the ASM instance fails, an Oracle instance resource error will be detected, so userApplication will be switched to the standby node, and ongoing operations will never be disrupted.
Scalable operation
Do not create an ASM instance resource if ASM is used for Oracle RAC 10g or later. The ASM instance will be controlled by Oracle Clusterware.
Creation and configuration of ASM instances
Operation node
The ASM instance and database are only created on the operating node. The standby nodes will only operate the database on the shared disk of the operating node.
Note
ASM instance name must begin with “+”. The default name is “+ASM”.
See
Refer to the Oracle manual.
Standby node
Set up the standby nodes in the same configuration (directory creation, file copy, and links) as the operating node where the AMS instance and database are created.
Under $ORACLE_HOME/dbs
Under $ORACLE_BASE/admin/$ORACLE_SID
Under $ORACLE_BASE/admin/<ASM instance name>
$ORACLE_BASE/diag/asm (Oracle 11g)
The access privilege to the directories and files must be also the same as that on the operating node.
If you set where archive log is output on the operating node, it is necessary to set the same on the standby nodes.
Note
If required files on the operating node is backed up in the tar format with the /opt/FJSVclora/sbin/cloracpy command, configuration information of the ASM instance will not be backed up. Copy the following file manually in the tar format:
$ORACLE_BASE/admin/<ASM instance name>
ASM initialization parameter check
Check if the disk group in which the Oracle database is created is set for the ASM instance initialization parameter “ASM_DISKGROUPS”.
See
For the initialized parameter of the ASM instance, see the Oracle manual.
userApplication creation
When creating userApplication, create an ASM instance resource and Oracle instance resource. Register them in each userApplication.
Information
The NULLDETECTOR attribute is automatically set to the flag of the ASM instance resource. This value cannot be changed.
A disk group that is used for the ASM instance must not be mounted or unmounted manually. If the disk group is mounted, the following message might be output to the console when the ASM resource is activated, but no action needs to be taken.
ORA-15032: not all alterations performed
ORA-15017: diskgroup “diskgroup name” cannot be mounted
ORA-15030: diskgroup name “diskgroup name” is in use by another diskgroup
