Consider the following command to add a new disk group called “tdgroupA” with two failover groups:
CREATE DISKGROUP tdgrouopA NORMAD REDUNDANCY
FAILOVERGROUP control01 DISK
FAILOVERGROUP control02 DISK
The disk “/devices/A1” is currently a member disk of a disk group by name “tdgroup1”
Which task would be accomplished by the command?
The command would result in an error because a disk group can have only one failover group.
This command would result in an error because /devices/A1 disk is a member of another disk group tdgroup1.
A new disk group called tdgroupA will be added with two fialover groups and the /devices/A1 disk will get reattached to the new disk group without being detached from the existing one.
A new disk group called tdgroupA will be added with two failover groups and the /devices/A1 disk will be ignored for the new disk group because it is a member of an existing disk group tdgroup1.
A new disk group called tdgroupA will be added with two failover groups and the /devices/A1 disk gets detached from the existing disk group tdgroup1 and attached to the new disk group tdgroupA disk group.
You use the ADD clause of the ALTER DISKGROUP statement to add disks to a diskgroup, or to add a failure group to the disk group. The ALTER DISKGROUP clauses that you can use when adding disks to a disk group are similar to those that can be used when specifying the disks to be included when initially creating a disk group. Because no FAILGROUP clauses are included in the ALTER DISKGROUP statement, each disk is assigned to its own failure group. The NAME clauses assign names to the disks, otherwise they would have been assigned system-generated names. Therefore, the following statement would fail because /devices/diskA1 already belong to tdgroup1.
REF.: Oracle(r) 10g Administrator Guide , 12-21