OCP Oracle 10g Admin II - Ch 9 : Understanding Automatic Storage Management

Chapter 9 - Understanding Automatic Storage Management

Review Questions

1. Extents in an ASM file are allocated in units of which size?
A. 100KB
B. 10MB
C. 1MB
D. 64KB
----
Ans: C.
ASM disks are partitioned in allocation units of one megabyte each.

2. To prevent connections to an ASM instance, you can use which of the
following commands? (Choose the best answer.)
A. ALTER SYSTEM ENABLE RESTRICTED SESSION
B. SHUTDOWN IMMEDIATE
C. ALTER SYSTEM DISABLE CONNECTIONS
D. ALTER DATABASE ENABLE RESTRICTED SESSION
----
Ans: A.
Similar to an RDBMS instance, you can use ALTER SYSTEM ENABLE RESTRICTED SESSION to prevent connections to the instance. While SHUTDOWN IMMEDIATE will prevent connections to the ASM instance, this is most likely overkill if all you want to do is temporarily prevent connections. Choices C and D are not valid commands and will generate an error message.

3. Which initialization parameter in an ASM instance specifies the disk groups to
be automatically mounted at instance startup?
A. ASM_DISKMOUNT
B. ASM_DISKGROUP
C. ASM_DISKSTRING
D. ASM_MOUNTGROUP
----
Ans: B.
The initialization parameter ASM_DISKGROUP, valid only in an ASM instance, specifies the disk groups to be automatically mounted when the ASM instance starts. ASM_DISKSTRING is operating system dependent and restricts the file system devices
that can be used to create disk groups. ASM_DISKMOUNT and ASM_MOUNTGROUP are not valid initialization parameters.

4. Which of the following command options is not valid for an ASM instance?
A. STARTUP OPEN
B. STARTUP NOMOUNT
C. STARTUP MOUNT
D. STARTUP OPEN RESTRICT
E. SHUTDOWN ABORT
---
Ans: A.
An ASM instance can be started up and shut down in the same way that an RDBMS database can, except that an ASM instance cannot be in the OPEN state because it does not have a data dictionary or a control file.

5. When an ASM instance receives a SHUTDOWN NORMAL command, what
command does it pass on to all database instances that rely on the ASM
instance's disk groups?
A. TRANSACTIONAL
B. IMMEDIATE
C. ABORT
D. NORMAL
E. None of the above
---
Ans: D.
When an ASM instance receives a SHUTDOWN command, it passes the same option
(NORMAL, IMMEDIATE or TRANSACTIONAL) to all database instances that rely on the
ASM instance for disk group services.


6. When creating a disk group, what keyword must be specified if you need to
reuse a disk that has previously been used as part of another disk group?
A. NOFORCE
B. REUSE
C. USE
D. FORCE
E. INCLUDING CONTENTS
---
Ans: D.
You must use FORCE if the disk has previously been used as part of a disk group. If
the disk has never been used as part of a disk group, using the FORCE keyword returns
an error.

7. Which of the following ASM file templates is not striped as fine?
A. FLASHBACK
B. ARCHIVELOG
C. CONTROLFILE
D. ONLINELOG
----
Ans: B.
Files such as ARCHIVELOG files use coarse-grained striping. Fine striping stripes
the files every 128KB while coarse striping stripes the files every 1MB. All file types
with the exception of FLASHBACK, CONTROLFILE, and ONLINELOG are striped coarse.

8. You want to migrate your database to ASM, so you've done a clean shutdown,
made a closed backup of the entire database, noted the location of your control
files and online redo log files, and changed your SPFILE to use OMF. The last
step is running an RMAN script to do the conversion. Using the following
steps, what is the correct order in which the following RMAN commands
should be executed?
1. STARTUP NOMOUNT
2. ALTER DATABASE OPEN RESETLOGS
3. SQL "ALTER DATABASE RENAME ‘logfile1 path’ TO ‘+dgrp4 ‘"
# plus all other log files
4. SWITCH DATABASE TO COPY
5. BACKUP AS COPY DATABASE FORMAT ‘+dgrp4’
6. ALTER DATABASE MOUNT
7. RESTORE CONTROLFILE FROM ‘controlfile_location’
A. 2, 5, 3, 1, 7, 6, 4
B. 1, 7, 6, 5, 4, 3, 2
C. 5, 1, 2, 7, 4, 6, 3
D. 7, 3, 1, 5, 6, 2, 4
---
Ans: B.
After the RMAN script is run and the database is up and running successfully, you
may delete the old database files.


9. How can you reverse the effects of an ALTER DISKGROUP ... DROP DISK
command if it has not yet completed?
A. Issue the ALTER DISKGROUP ... ADD DISK command.
B. Issue the ALTER DISKGROUP ... UNDROP DISKS command.
C. Issue the ALTER DISKGROUP ... DROP DISK CANCEL command.
D. Retrieve the disk from the recycle bin after the operation completes.
--
Ans: B.
If the DROP DISK operation has not yet completed, you can cancel and roll back
the entire DROP DISK operation by using ALTER DISKGROUP ... UNDROP DISKS, with
the disk group still being continuously available to all users.

10. To reference existing ASM files, you need to use a fully qualified ASM
filename. Your development database has a disk group named DG2A, the
database name is DEV19, and the ASM file that you want to reference is a
datafile for the USERS02 tablespace. Which of the following is a valid ASM
filename for this ASM file?

A. dev19/+DG2A/datafile/users02.701.2
B. +DG2A/dev19/datafile/users02.701.2
C. +DG2A/dev19/users02/datafile.701.2
D. +DG2A.701.2
E. +DG2A/datafile/dev19.users.02.701.2
---
Ans: B.
A fully qualified existing ASM filename has the format
+group/dbname/filetype/tag.file.incarnation. In this case, filetype is
datafile, and tag is the tablespace name to which it belongs, or users02.

11. Which background process coordinates the rebalance activity for disk groups?
A. ORBn
B. OSMB
C. RBAL
D. ASMn
----
Ans: C.
RBAL coordinates rebalance activity for a disk group in an ASM instance, ORBn
actually performs the extent movement in an ASM instance, and OSMB acts as a
bridge between the ASM instance and the RDBMS instance. There is no such process
name ASMn.


12. On the development database rac0 there are six raw devices: /dev/raw/raw1
through /dev/raw/raw6. /dev/raw/raw1 and /dev/raw/raw2 are 8GB each,
and the rest are 6GB each. An existing disk group +DATA1, of NORMAL
REDUNDANCY, uses /dev/raw/raw1 and /dev/raw/raw2. Which series of the
following commands will drop one of the failure groups for +DATA1, create a
new disk group +DATA2 using two of the remaining four raw devices, and then
cancel the drop operation from +DATA1?
A. ALTER DISKGROUP DATA1 DROP DISK DATA1_0001;
CREATE DISKGROUP DATA2 NORMAL REDUNDANCY
FAILGROUP DATA1A DISK '/dev/raw/raw3'
FAILGROUP DATA1B DISK '/dev/raw/raw4';
ALTER DISKGROUP DATA1 UNDROP DISKS;

B. ALTER DISKGROUP DATA1 DROP DISK DATA1_0001;
CREATE DISKGROUP DATA2 HIGH REDUNDANCY
FAILGROUP DATA1A DISK '/dev/raw/raw3'
FAILGROUP DATA1B DISK '/dev/raw/raw4'
ALTER DISKGROUP DATA1 UNDROP DISKS;

C. ALTER DISKGROUP DATA1 DROP DISK DATA1_0001;
CREATE DISKGROUP DATA2 NORMAL REDUNDANCY
FAILGROUP DATA1A DISK '/dev/raw/raw3'
FAILGROUP DATA1B DISK '/dev/raw/raw4';
ALTER DISKGROUP DATA1 UNDROP DATA1_0001;

D. ALTER DISKGROUP DATA1 DROP DISK DATA1_0001
ADD DISKGROUP DATA2 NORMAL REDUNDANCY
FAILGROUP DATA1A DISK '/dev/raw/raw3'
FAILGROUP DATA1B DISK '/dev/raw/raw4';
ALTER DISKGROUP DATA1 UNDROP DISKS;
-----
Ans: A.
Note that the UNDROP operation will cancel a drop operation in progress but cannot
reverse a drop operation that has already completed. For HIGH REDUNDANCY, at least
three failure groups must be specified. While you can combine a drop and add
operation into one command, the command can reference only one disk group.

13. Which type of database file is spread across all disks in a disk group?
A. All types of files are spread across all disks in the disk group.
B. Datafiles
C. Redo log files
D. Archived redo log files
E. Control files
---
Ans: A.
All types of database files are spread across all disks in the disk group to ensure
redundancy unless the redundancy is set to EXTERNAL.

14. How can you reverse the effects of an ALTER DISKGROUP ... DROP DISK
command if it has already completed?
A. Issue the ALTER DISKGROUP ... ADD DISK command.
B. Issue the ALTER DISKGROUP ... UNDROP DISKS command.
C. Issue the ALTER DISKGROUP ... DROP DISK CANCEL command.
D. Retrieve the disk from the recycle bin after the operation completes.
---
Ans: A. If the DROP DISK operation has already completed, you must use ALTER
DISKGROUP ... ADD DISK to add the disk back to the disk group. In any case, the disk
group is continuously available to all users.

15. Which of the following ALTER DISKGROUP commands does not use
V$ASM_OPERATION to record the status of the operation?
A. ADD DIRECTORY
B. DROP DISK
C. RESIZE DISK
D. REBALANCE
E. ADD FAILGROUP
----
Ans: A.
The ADD DIRECTORY command does not use V$ASM_OPERATION to track its
progress, because this operation adds only a small amount of metadata - a directory
object - to the disk group and takes a minimal amount of time to complete.

16. If you use ALTER DISKGROUP ... ADD DISK and specify a wildcard for the
discovery string, what happens to disks that are already a part of the same or
another disk group?
A. The command fails unless you specify the FORCE option.
B. The command fails unless you specify the REUSE option.
C. The command must be reissued with a more specific discovery string.
D. The other disks already part of the disk group are ignored.
---
Ans: D.
The ALTER DISKGROUP ... ADD DISK command adds all disks that match the
discovery string but are not already part of the same or another disk group.

17. Choose the set of the following initialization parameters that is valid and
recommended for an ASM instance.
A. INSTANCE_TYPE=RDBMS
ASM_POWER_LIMIT=2
LARGE_POOL_SIZE=8MB
DB_UNIQUE_NAME=+ASM
ASM_DISKGROUPS=DATA1,DATA2


B. INSTANCE_TYPE=ASM
ASM_POWER_LIMIT=2
LARGE_POOL_SIZE=8MB
DB_UNIQUE_NAME=+ASM
ASM_DISKGROUPS=DATA1,DATA2

C. INSTANCE_TYPE=ASM
ASM_POWER_LIMIT=15
LARGE_POOL_SIZE=8MB
DB_UNIQUE_NAME=+ASM
ASM_DISKGROUPS=DATA1,DATA2

D. INSTANCE_TYPE=ASM
ASM_POWER_LIMIT=2
LARGE_POOL_SIZE=4MB
DB_UNIQUE_NAME=+ASM
ASM_DISKGROUPS=DATA1,DATA2
---
Ans: B.
The INSTANCE_TYPE for an ASM instance is ASM; otherwise, it is RDBMS, whether it
uses ASM or not. The ASM_POWER_LIMIT command controls the speed of a disk
group rebalance, but its maximum value is 11. For an ASM instance, the minimum
recommended value for LARGE_POOL_SIZE is 8MB.


18. Which of the following scenarios concerning ASM instance shutdown is correct?
A. When an ASM instance is shut down with NORMAL, IMMEDIATE, or
TRANSACTIONAL, the same shutdown command is passed to the
dependent instances and the ASM instance waits for all dependent
instances to shut down before it shuts down.
B. When an ASM instance shuts down with NORMAL, an alert is sent to all
dependent instances, notifying the DBA to shut down the dependent
instances manually before the ASM instance shuts down.
C. When an ASM instance shuts down with the TRANSACTIONAL option,
all dependent instances shut down with NORMAL, IMMEDIATE, or
TRANSACTIONAL, depending on the dependent database's default.
D. When an ASM instance is shut down with NORMAL, IMMEDIATE, or
TRANSACTIONAL, the same shutdown command is passed to the
dependent instances and the ASM instance does not wait for all
dependent instances to shut down before it shuts down.
E. When an ASM instance shuts down with the IMMEDIATE option, the
ASM instance shuts down immediately and all dependent instances
shut down with ABORT.
---
Ans: A.
When an ASM instance shuts down with NORMAL, IMMEDIATE, or TRANSACTIONAL,
the same shutdown option is passed to all dependent instances and the ASM instance
waits for the dependent instances to shut down before shutting itself down. If an
ASM instance shuts down with ABORT, it immediately shuts down, the dependent
instances lose their connection to the ASM instance, and as a result, they shut down
with ABORT either before or after the ASM instance shuts down completely.

19. A database can create datafiles in how many different disk groups? (Choose
the best answer.)
A. Each datafile in the database can reside in a different disk group.
B. One
C. Disk groups manage tablespaces, not datafiles.
D. A maximum of two, one for SYSTEM and SYSAUX and the other tablespaces in another disk group.
---
Ans: A.
Each database datafile can reside in a different disk group; each disk group can
also contain datafiles from other databases.


20. ASM supports all of the following file types except for which of the
following? (Choose all that apply.)
A. Database files
B. SPFILEs
C. Redo log files
D. Archived log files
E. RMAN backup sets
F. Password files
G. init.ora files
---
Ans: F, G.
ASM supports datafiles, log files, control files, archive logs, RMAN backup
sets, SPFILEs, and other Oracle database file types, but not password files or
init.ora files.