1Z0-902 Online Practice Questions and Answers

Correct Answer: D

Explanation: Exadata Secure RDMA Fabric isolation is a feature that allows you to use virtualization on the X9M-2 platform while maintaining security and isolation between multiple tenants or VM clusters. Secure Fabric isolation works by creating a dedicated network partition and VLAN ID for each Database VM cluster, which is used for cluster networking between the database servers in the VM Cluster. This ensures that the network traffic of each VM cluster is isolated from the others, and it prevents unauthorized access to the data or resources of other VM clusters. Secure Fabric isolation can also be used for other purposes such as client networking, Data Guard traffic, but it's mainly used to provide security and isolation between multiple tenants or VM clusters.

According to Oracle's documentation1, Exadata Secure RDMA Fabric Isolation is a feature that enables strict network isolation for Oracle Real Application Clusters (Oracle RAC) clusters on Exadata Database Machine systems that use RDMA over Converged Ethernet (RoCE). Exadata Secure RDMA Fabric Isolation uses RoCE VLANs to ensure that network packets from one VM cluster cannot be seen by another VM cluster. VLAN tag enforcement is done at the KVM host level, which means that security cannot be bypassed by any software exploits or misconfiguration on the database server VMs1. Therefore, the statement that is true about how Exadata Secure RDMA Fabric isolation is used in X9M-2 with virtualization enabled is: With Secure Fabric isolation, each Database VM cluster uses a dedicated network partition and VLAN ID for cluster networking between the database servers in the VM Cluster. This provides security and isolation between multiple tenants or VM clusters.

Correct Answer: CD

Explanation: According to the Oracle documentation1, two monitoring tools that might be useful in examining I/O performance for the prod database are:

cellcli (or exacli/exadcli) to examine storage server metrics such as database, category, ceiidisk, and griddisk (D). This tool can help you monitor the I/O Resource Management (IORM) metrics and identify any bottlenecks or imbalances in the

storage layer.

I/O-specific dynamic performance views such as v$iostat_fiie, v$iostat_function, and v$iostat_consumer_group from the prod database instances using SQL *p1us ? These views can help you monitor the I/O activity and latency at the file,

function, and consumer group level.

Correct Answer: AC

A. YOU query VSSYSTEM_EVENTS and filter for the event `cell physical IO interconnect bytes returned by smart scan', associated to your table. This does not show how much data was filtered by Smart Scan, but only how much data was returned after Smart Scan12.

C. You query v$SYSTAT and filter for the statistic `cell smart table scan', associated to your table. This does not show how much data was filtered by Smart Scan for a specific table, but only for all tables in a session12. https:// www.databasejournal.com/oracle/monitoring-smart-scans-in-oracle-exadata/

Correct Answer: AF

Explanation: According to Oracle's documentation12, some of the statements that are true about applying updates on Exadata systems are:

Failed storage server updates are automatically rolled back to a previous release1. When running a "yum update" for a new Exadata release, all other repositories should be disabled1.

Correct Answer: ACEG

Explanation: According to the Oracle Auto Service Request (ASR) documentation1, ASR raises service requests for qualified Oracle products that are detected with specific faults. The qualified Exadata products include2:

Database servers

Storage servers

InfiniBand switches

Cisco switches (X8M and later systems)

Power distribution units (PDUs)

Correct Answer: A

Explanation: According to 1, Exadata X9M-2 Database Servers are based on Intel Xeon Platinum 8368Y processors with 32 cores and 768 GB of DRAM memory per server. This memory can be expanded up to 1.5 TB per server by adding 24 x 32 GB DIMMs. The DRAM memory is used for buffer cache, PGA, and other database purposes1. Exadata X9M-2 Database Servers also have 25.6 TB of Persistent Memory Acceleration (PMEM) per server, which is used for log writes and columnar data caching1. PMEM is a new type of memory that combines the speed of DRAM with the persistence of flash2. Exadata X9M- 2 Database Servers are designed to run Oracle Database workloads with high performance, scalability, and reliability2

Correct Answer: ACE

Explanation: According to Oracle.com documents or resources, the three options that are available for database consolidation on Exadata are:

A. Multiple pluggable databases in one or more container databases on a Virtual Machine or Bare Metal cluster123.

C. A single database with one or more schema per application12.

E. Multiple Databases on a cluster12. https://blogs.oracle.com/exadata/post/database-consolidation-why-and-how

Correct Answer: C

Oracle KVM Guest: This is a virtual machine that runs on top of Oracle Linux KVM hypervisor. It can be used to run Oracle Database or other applications on Exadata Database Machine2. Therefore, it runs on the Database Servers. Oracle Enterprise Manager Agent (OMA): This is a software agent that communicates with Oracle Enterprise Manager Cloud Control and provides monitoring and management capabilities for Exadata Database Machine2. Therefore, it runs on both Database Servers and Storage Servers. ASM instance: This is an instance of Oracle Automatic Storage Management (ASM), which is a volume manager and a file system for Oracle Database files. It manages diskgroups that span across multiple Storage Servers2. Therefore, it runs on the Database Servers. RDBMS instance: This is an instance of Oracle Database that processes SQL statements and executes transactions. It uses ASM disk groups to store data files, control files, redo log files, etc2. Therefore, it runs on the Database Servers. Automatic Diagnostic Repository Command Interpreter (ADRCI): This is a command-line tool that enables you to view diagnostic data stored in the Automatic Diagnostic Repository (ADR). ADR is a file-based repository for database diagnostic data such as trace files, alert logs, etc2. Therefore, ADRCI runs on both Database Servers and Storage Servers, depending on where the ADR is located. CELLCLI: This is a command-line interface that enables you to configure and manage Exadata Storage Server Software. It allows you to perform tasks such as creating disk groups, monitoring cell health, applying patches, etc2. Therefore, it runs on the Storage Servers. Cell Server(CELLSRV): This is a process that runs on each Storage Server and handles I/O requests from the Database Servers. It implements Exadata Smart Scan , which offloads data-intensive SQL operations from the Database Servers to the Storage Servers2. Therefore, it runs on the Storage Servers. diskmon: This is a process that monitors the status of disks and flash devices on each Storage Server. It reports disk failures and performs automatic disk reclamation2. Therefore, it runs on the Storage Servers. Restart Server (RS): This is a process that manages automatic restarts of critical processes such as CELLSRV , MS , or OMA in case of failures. It also handles graceful shutdowns and startups of all processes on each server2. Therefore, it runs on both Database Servers and Storage Servers. Management Server (MS): This is a process that provides management services for each server such as collecting metrics , logging events , executing commands from CELLCLI , etc2. Therefore, it runs on both Database Servers and Storage Servers

Correct Answer: A

Explanation: The steps and the order in which they should be executed to create an ACFS Filesystem for use as a staging area for data loads are: asmcrad volcreate -G data -s 1024G acfs_dataload_vol : This command creates a new volume in the data diskgroup, with a size of 1024 GB, and named acfs_dataload_vol. asmcmd vol info -G data acfs_dataload_vol | grep Device: This command will show the device name of the newly created volume /usr/sbin/mkfs -t acfs /dev/asm/ac:fs_dataload_vol-123: This command creates a new ACFS filesystem on the volume created in step 1 sudo /u01/app/19.0.0.0/grid/bin/srvctl start filesystem -device /dev/asn/acfs_dataload_vol-123: This command starts the filesystem created in step 3 sudo chovn -R oracle:dba /mnt/acfs_dataload_vol: This command changes the ownership of the /mnt/acfs_dataload_vol to the oracle:dba user. /sbin/acfsutil snap create -v data_load /mnt/acfs_dataload_vol: This command creates a snapshot of the filesystem to be used as a staging area. acfsutil size +2S0G -d /dev/asm/acfs_dataload_vol-123 /mnt/acfs_dataload_vol/ : This command increases the size of the filesystem by 2GB /u01/app/19-G.O-Q7grid/bin/srvctl add filesystem -device /dev/asm/acfs_dataload_vol-

Correct Answer: AD

Explanation: According to the Oracle documentation1, two statements that are true about enabling write-back flash cache are:

Write-back flash cache is on by default for High Capacity Storage Servers in High Redundancy configurations (A). This is because write-back flash cache provides better performance and reliability for data file writes than write-through flash

cache. Before write-back flash cache is enabled, you need to drop the Flash Cache first (D). This is because changing the flash cache mode requires recreating the flash cache with a different configuration.