Datasheet

Answers to Review Questions

1. A, B, C. Option A is correct because ASM makes administration and maintenance of

disks much easier. Option B is correct because ASM provides for load balancing across the

physical disks for better performance. Answer C is correct because ASM provides RAID-1

redundancy via double or triple mirrors.

2. A, B, E. Option A is correct because the SGA is allocated when the ASM instance is

started. Option B is correct because the Oracle processes are also started when the ASM

instance is started. Option E is correct because the ASM instance requires either a param-

eter ﬁle or an spﬁle.

3. A. When a disk fails, it is taken ofﬂine immediately but it is not dropped at that time. By

default, you will have 3.6 hours to correct the problem before ASM will automatically drop

the disk. You can conﬁgure this time by modifying the disk attributes.

4. C. Increasing the value of ASM_POWER_LIMIT will increase the degree of parallelism of the

rebalance operation, which may help to increase the performance of that operation.

5. E. The default AU size is 1MB, and 64MB is the maximum AU size for a disk group.

6. 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.

7. E. If you do a normal shutdown of the ASM instance, an error will be returned if any Oracle

database is using that ASM instance. Use the shutdown abort command to force the ASM

instance to shut down. This will cause all other Oracle databases attached to the ASM instance

to be shut down with the equivalent of a shutdown abort command.

8. D. The ASM_DISKSTRING parameter is not set correctly. When the ASM instance is started,

it will use the ASM_DISKSTRING to do ASM disk discovery. Correct the ASM_DISKSTRING

parameter, and restart the instance to correct the problem.

9. C. High redundancy is the highest redundancy setting available in ASM, or to the Alliance

in this case. This will result in a double-mirrored ASM disk group.

10. B. After the RMAN script is run and the database is up and running successfully, you may

delete the old database ﬁles.

11. 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.

12. B. A fully qualiﬁed existing ASM ﬁlename has the format +group/dbname/filetype/tag

.f ile.in car n at io n . In this case, filetyp e is datafile, and tag is the tablespace name to

which it belongs, or users02.

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