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Question 1:

You want to perform the following operations for the DATA ASM disk group:
• Verify the consistency of the disk.
• Cross-check all the file extent maps and allocation tables for consistency.
• Check whether the alias metadata directory and file directory are linked correctly.
• Check that ASM metadata directories do not have unreachable allocated blocks.
Which command accomplishes these tasks?

A. ALTER DISKGROUP data CHECK;
B. ALTER DISKGROUP data CHECK DISK;
C. ALTER DISKGROUP data CHECK FILE;
D. ALTER DISKGROUP data CHECK DISK IN FAILURE GROUP

Answer: A 

Explanation:
Syntax: ALTER DISKGROUP <disk_group_id> CHECK [REPAIR | NOREPAIR];
The check_diskgroup_clause lets you verify the internal consistency of Oracle ASM disk group
metadata. The disk group must be mounted. Oracle ASM displays summary errors and writes the
details of the detected errors in the alert log.
The CHECK keyword performs the following operations:
• Checks the consistency of the disk.
• Cross checks all the file extent maps and allocation tables for consistently.
• Checks that the alias metadata directory and file directory are linked correctly.
• Checks that the alias directory tree is linked correctly.
• Checks that Oracle ASM metadata directories do not have unreachable allocated blocks.
Refer to here


Question 2:

Which two statements are true regarding the functionality of the remap command in ASMCMD?
(Choose two.)

A. It repairs blocks that have read disk I/O errors.
B. It checks whether the alias metadata directory and the file directory are linked correctly.
C. It repairs blocks by always reading them from the mirror copy and writing them to the original
location.
D. It reads the blocks from a good copy of an ASM mirror and rewrites them to an alternate location
on disk if the blocks on the original location cannot be read properly.

Answer: A, D

Explanation:
Reference from the Oracle document release v11.1 at here:
Repairs a range of physical blocks on a disk. The remap command only repairs blocks that have read
disk I/O errors. It does not repair blocks that contain corrupted contents, whether or not those
blocks can be read. The command assumes a physical block size of 512 bytes and supports all
allocation unit sizes (1 to 64 MB).
Reference from the Oracle document release v11.2 at here:
The remap command marks a range of blocks as unusable on the disk and relocates any data
allocated in that range.


Question 3:

What is the advantage of setting the ASM-preferred mirror read for the stretch cluster configuration?

A. It improves resync operations.
B. This feature enables much faster file opens.
C. It improves performance as fewer extent pointers are needed in the shared pool.
D. It improves performance by reading from a copy of an extent closest to the node.

Answer: D

Explanation:
Preferred Read Failure Groups
When you configure Oracle ASM failure groups, it might be more efficient for a node to read from an
extent that is closest to the node, even if that extent is a secondary extent. In other words, you can
configure Oracle ASM to read from a secondary extent if that extent is closer to the node instead of
Oracle ASM reading from the primary copy which might be farther from the node. Using the
preferred read failure groups feature is most useful in extended clusters.


Question 4:

Examine the following command:
ALTER DISKGROUP data MOUNT FORCE;
In which scenario can you use the above command to mount the disk group?
A. when ASM disk goes offline
B. when one or more ASM files are dropped
C. when some disks in a disk group are offline
D. when some disks in a failure group for a disk group are rebalancing

Answer: C

Explanation:
In the FORCE mode, Oracle ASM attempts to mount the disk group even if it cannot discover all of
the devices that belong to the disk group. This setting is useful if some of the disks in a normal or
high redundancy disk group became unavailable while the disk group was dismounted. When
MOUNT FORCE succeeds, Oracle
ASM takes the missing disks offline.
If Oracle ASM discovers all of the disks in the disk group, then MOUNT FORCE fails. Therefore, use
the MOUNT FORCE setting only if some disks are unavailable. Otherwise, use NOFORCE.
In normal- and high-redundancy disk groups, disks from one failure group can be unavailable and
MOUNT FORCE will succeed. Also in high-redundancy disk groups, two disks in two different failure
groups can be unavailable and MOUNT FORCE will succeed. Any other combination of unavailable
disks causes the operation to fail, because Oracle ASM cannot guarantee that a valid copy of all user
data or metadata exists on the available disks.
Refer to here


Question 5:

Which background process of a database instance, using Automatic Storage Management (ASM),
connects as a foreground process into the ASM instance?

A. ASMB
B. PMON
C. RBAL
D. SMON

Answer: A

Explanation:
ASMB (ASM Background Process): Communicates with the ASM instance, managing storage and
providing statistics, runs in ASM instances when the ASMCMD cp command runs or when the
database instance first starts if the server parameter file is stored in ASM. ASMB also runs with
Oracle Cluster Registry on ASM.
RBAL (ASM Rebalance Master Process): In an ASM instance, it coordinates rebalance activity for disk
groups. In a database instances, it manages ASM disk groups.
PMON (Process Monitor): Monitors the other background processes and performs process recovery
when a server or dispatcher process terminates abnormally.
SMON (System Monitor Process): Performs critical tasks such as instance recovery and dead
transaction recovery, and maintenance tasks such as temporary space reclamation, data dictionary
cleanup, and undo tablespace management