1Z0-902 Online Practice Questions and Answers

Correct Answer: B

Explanation: https://docs.oracle.com/en/engineered-systems/exadata-database- machine/dbmso/new-features-exadata-system-software-release-23.html

Correct Answer: A

Your customer needs to ensure that their data is available on the Exadata machine during updates. The customer wants to be able to update one server at a time but still be protected against single-node server failure. This means that they need a redundancy level that can tolerate at least one disk failure without losing data availability or performance. Therefore, the best option for them is normal redundancy . Normal redundancy provides two-way mirroring by default, which means that each data extent has a primary copy and a mirror copy on different disks in different failure groups1. A failure group is a subset of disks within a disk group that are likely to fail at the same time due to common dependencies2. On Exadata Database Machine , each Storage Server is considered as a failure group by default2. This means that if one Storage Server fails or needs to be updated , the data on its disks can still be accessed from another Storage Server that has the mirror copies of the same data extents2. Therefore, normal redundancy ensures data availability and performance during updates or single-node server failures. https://docs.oracle.com/en/engineered-systems/exadata-databasemachine/sagug/exadata-administering-asm.html

Correct Answer: C

Explanation: According to Oracle's documentation1, the Cell Control Command-Line Interface (CellCLI) utility is the command-line administration tool for Oracle Exadata System Software. It can be used to perform various tasks on Exadata Storage Servers, such as creating and managing objects, monitoring performance, and configuring alerts. To run CELLCLI commands on multiple cells simultaneously, you can use the Distributed Command-Line Interface (dcli) utility2. The dcli utility allows you to execute commands or scripts on a group of cells or hosts in parallel. You can use the dcli utility to copy files from one cell or host to multiple cells or hosts using the -f option3. You can also use the dcli utility to execute commands or scripts on multiple cells or hosts using the -l option to specify a user name and the -g option to specify a file containing a list of cells or hosts3. Therefore, to achieve your requirement of running a script with several CELLCLI commands on each cell in your Exadata full rack simultaneously, you must: Copy and execute the script on all storage servers using the dcli command.

Correct Answer: CD

C. OEDA deployment steps include calibrate cells, create cell disks, and resecure machine2.

D. OEDA sets up key-based authentication for the root user by using the setuprootssh.sh utility included with OEDA2.

Correct Answer: AC

The CELLCLI CALIBRATE command can be used to check the health of all flash cards in the storage server, and it should be run after logging in as the celladmin user. The hardware monitoring using the storage server ILOM should also be used to check for errors and other potential issues with the flash cards. The CELLCLI list LUN DETAIL command should not be used to identify a damaged or failing flash card, since it will not provide any information about the health of the flash card. https://docs.oracle.com/en/engineered-systems/exadata-database- machine/dbmmn/index.html

Correct Answer: AE

Explanation: Exadata storage realms using ASM-scoped security mode allows you to control which database can access which griddisks by creating realms at the ASM level, thereby allowing you to limit the access of each database to the griddisks that it needs to access. This is covered in section 3.15.2 of the Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book and Resources [1]. Exadata storage realms using database-scoped security mode allows you to control which database can access which griddisks by creating realms at the database level [1], thereby allowing you to limit the access of each database to the griddisks that it needs to access. This is covered in section 3.15.3 of the Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book and Resources [2]. [1] https://docs.oracle.com/en/engineered-systems/exadata-database-machine/x9m/exad- implementing-database-machinex9m.pdf [2] https://docs.oracle.com/en/engineered- systems/exadata-database-machine/x9m/exad-implementing-database-machine-x9m.pdf

Correct Answer: AE

Explanation: A and E are the two correct quarantine types that can disable Smart Scan for multiple databases that offload SQL statements to a cell on an Exadata Database Machine. A is correct because SQL Plan Quarantine will disable Smart Scan for all queries related to the SQL plan that was placed in the SQL Plan Quarantine [1]. E is correct because the Cell Offload Quarantine will disable Smart Scan for all queries offloaded to Oracle Database Exadata Storage Server Software [2]. The other statements (B, C, and D) are incorrect. [1] Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book , Chapter 13 [1][2]: Oracle Database Exadata Storage Server Software [2] Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book , Chapter 15 [1][2]: Oracle Database Exadata Storage Server Configuration https://docs.oracle.com/en/engineered-systems/exadata-database- machine/sagug/exadata-storage-server-software-introduction.html

Correct Answer: B

Explanation: According to Oracle's documentation12, ASM failure groups provide redundancy by storing mirror copies of data on different disks or storage servers. When ASM allocates an extent for a normal redundancy file, ASM allocates a

primary copy and a secondary copy. ASM chooses the disk on which to store the secondary copy so that it is in a different failure group than the primary copy1. This way, if one disk or storage server fails, ASM can still access the data from

another failure group2. Therefore, the statement that is true about how ASM failure groups provide redundancy is:

Failure groups contain all ASM disks in a single storage server preventing mirror copies being written to the same storage server.

Correct Answer: C

Explanation: The dbmcli -e "LIST IBPORT DETAIL" command is not valid on Exadata X9M. According to the Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book [1][2], this command is only valid on Exadata X3 and X4 models. The other three commands are valid on Exadata X9M. https://forums.oracle.com/ords/apexds/map/tech/apps- infra/discussion/4342715/monitoring-roce-performance

Correct Answer: A

Explanation: This SQL statement is adding the new griddisks to the existing diskgroup "DATA" and creating one new failgroup, consisting of all 96 griddisks. The "REBALANCE POWER 512" option tells the system to perform a rebalance operation with a power of 512. It means the system distributes the data evenly across all the disks in the diskgroup using a power of 512.