Oracle Database 12c: RAC and Grid Infrastructure Administration 試験
Question No : 1
Examine this output:
The ACFS disk group has 10 GB free space and the file system is currently mounted.
You execute this command to increase the volume size:
ASMCMD >volresize CG ACFS Cs 3G VOL1
Which statement is true regarding the outcome?
If there is an Oracle ACFS file system on the volume, then you cannot resize the volume with the volresize command. You must use the acfsutil size command, which also resizes the volume and file system.
Question No : 2
Which two tasks must be performed before launching the Oracle universal installer to install Oracle Database Software for RAC?
Question No : 3
You administer a three-instance, policy-managed, multitenant RAC database CDB1 with two PDBs: PDB_1 and PDB_2.
Examine these commands executed on host01:
$ srvctl add service Cdb CDB1 Cpdb PDB_1 Cserverpool prod_pool Ccardinality singleton
$ srvctl start service Cdb CDB1 Cservice CRM
$ srvctl stop service Cdb CDB1 Cservice CRM
Which three statements are true?
Question No : 4
Which three statements are true concerning policy-based cluster management in Oracle 12c Clusterware?
C: Server pools divide the cluster into logical groups of servers hosting both singleton and uniform applications. The application can be a database service or a non-database application.
D: You manage server pools that contain Oracle RAC databases with the Server Control (SRVCTL) utility.
E: When Oracle Cluster ware is installed, two internal server pools are created automatically: Generic and Free. All servers in a new installation are assigned to the Free server pool, initially
Question No : 5
A Java application using thick JDBC connections will soon be deployed, and you must configure a RAC database to support highly available connections. Broken connections must be re-established as quickly as possible.
Which feature will support this requirement?
The Fast Connection Failover (FCF) feature is an Oracle RAC/Fast Application Notification (FAN) client implemented through the connection pool. The feature requires the use of an Oracle JDBC driver and an Oracle RAC database.
Question No : 6
The DGRP1 diskgroup has these attributes:
- Normal redundancy
- Two failgroups with four asmdisks in each failgroup
- compatible.asm set to 12.1
The ASM_POWER_LIMIT parameter is currently set to 1 in the ASM instances.
There are three databases whose instances are up and which access data in the DGRP1 diskgroup. No other clients use this diskgroup.
You want to add two asmdisks to each failgroup, complete the rebalance as quickly as possible, by avoiding checks for access to allocation units, and then restore database availability.
Examine the list of actions (see exhibit):
Identify the correct sequence of required steps:
Question No : 7
Which two statements are true about ASM alias names?
Question No : 8
Which three statements are true about ASM Cloud File System (ACFS) tagging?
A: The acfssettag command sets the tag name on an Oracle ACFS file.
Syntax sb8 acfssettag(const oratext *path, const oratext *tagname, oratext *value, size_t size, ub4 flags);
C: Oracle ACFS tagging assigns a common naming attribute to a group of files. Oracle ACFS Replication can use this tag to select files with a unique tag name for replication to a different remote cluster site. The tagging option avoids having to replicate an entire Oracle ACFS file system.
E: The acfsutil tag set command adds the given tag to the specified files or directories in an Oracle ACFS file system.
D: The acfsutil encr on command encrypts an Oracle ACFS file system, directories, or individual files.
However, you specify a directory not a tag name.
Question No : 9
Which three statements are true about Global Resource Management in an Oracle 12c RAC database?
B: Remastering is the term used that describes the operation whereby a node attempting recovery tries to own or master the resource(s) that were once mastered by another instance prior to the failure. When one instance leaves the cluster, the GRD of that instance needs to be redistributed to the surviving nodes. RAC uses an algorithm called lazy remastering to remaster only a minimal number of resources during a reconfiguration.
D: Using the SHUTDOWN TRANSACTIONAL command with the LOCAL option is useful to shut down a particular Oracle RAC database instance. Transactions on other instances do not block this operation.
C: Recovery from instance failure is automatic, requiring no DBA intervention. In case of instance failure, a surviving instance can read the redo logs of the failed instance. For example, when using the Oracle Parallel Server, another instance performs instance recovery for the failed instance. In single-instance configurations, Oracle performs crash recovery for a database when the database is restarted, that is, mounted and opened to a new instance. The transition from a mounted state to an open state automatically triggers crash recovery, if necessary.
A: After a NORMAL or IMMEDIATE shutdown, instance recovery is not required.
Question No : 10
PROD1, PROD2 and PROD3 are three active instances of the PROD database.
Examine these commands executed on PROD1:
SQL > ALTER SYSTEM SET PARALLEL_MIN_SERVERS=200 SCOPE=MEMORY sid=’*’;
SQL > ALTER SYSTEM SET PARALLEL_MIN_SERVERS=100 SCOPE=MEMORY sid=’PROD1’;
Which statement is true?
First SET PARALLEL_MIN_SERVERS is set to 200 for all instances, then it is set to 100 for PROD1.
Question No : 11
Which four tasks are performed by DBCA when you convert a single-instance database to a four-instance RAC database?
A: Create redo threads that have at least two redo logs for each additional instance.
B: If your single-instance database was using automatic undo management, then create an undo tablespace for each additional instance using the CREATE UNDO TABLESPACE SQL statement.
ABF: You can use Database Configuration Assistant to convert from single-instance Oracle databases to Oracle RAC. DBCA automates the configuration of the control file attributes, creates the undo tablespaces and the redo logs, and makes the initialization parameter file entries for cluster-enabled environments. It also configures Oracle Net Services, Oracle Clusterware resources, and the configuration for Oracle RAC database management for use by Oracle Enterprise Manager or the SRVCTL utility.
Question No : 12
Which three statements are true concerning the Automatic Workload Repository (AWR) in a RAC environment?
AWR snapshots are collect at database level. Oracle extends the AWR tool for RAC databases by adding the possibility to generate snapshots reports against the whole cluster database, some database instances of the cluster database, a specific database instance of the cluster database, statistics for a specific select query.
D: AWR_SNAPSHOT_TIME_OFFSET specifies an offset for the AWR snapshot start time. AWR snapshots normally start at the top of the hour (12:00, 1:00, 2:00, and so on). This parameter allows DBAs to specify an offset for the AWR snapshot start time.
E: CONTROL_MANAGEMENT_PACK_ACCESS specifies which of the Server Manageability Packs should be active. The following packs are available:
The DIAGNOSTIC pack includes AWR, ADDM, and so on.
- The TUNING pack includes SQL Tuning Advisor, SQL Access Advisor, and so on.
- The NONE value means that both packs are not available.
References: https://docs.oracle.com/cloud/latest/db112/REFRN/initparams018.htm#REFRN10325 http://www.oracle-class.com/?p=2409
Question No : 13
Examine this query and output:
SQL> select order_flag, cache_size, session_flag, keep_value,
2 from user_sequences where sequence_name = ‘SEQ1’;
O CACHE_SIZE S K
-- ------------------- -- --
Y 10 N N
Performance analysis revealed severe SQ enqueue contention on the SEQ1 sequence.
The SEQ1 sequence is incremented from all instances equally and is frequently used.
Which two statements should you execute to reduce SQ enqueue contention?
A: Increasing sequence caches improves instance affinity to index keys deriving their values from sequences. That technique may result in significant performance gains for multi-instance insert-intensive applications.
C: When creating sequences for a RAC environment, DBAs should use the noorder keyword to avoid an additional cause of SQ enqueue contention that is forced ordering of queued sequence values. In RAC, a best practice is to specify the “noordered” clause for a sequence. With a non-ordered sequence, a global lock not required by a node whenever you access the sequence.
Question No : 14
Which three statements are true about services when used with transparent application failover (TAF) for an administrator-managed RAC database?
A: SESSION failover. When the connection to an instance is lost, SESSION failover results only in the establishment of a new connection to another Oracle RAC node; any work in progress is lost. SESSION failover is ideal for online transaction processing (OLTP) systems, where transactions are small.
D: Oracle's answer to application failover is a new Oracle Net mechanism dubbed Transparent Application Failover. TAF allows the DBA to configure the type and method of failover for each Oracle Net client.
C. TAF only restart query not restart transaction.
TAF can restart a query after failover has completed but for other types of transactions, such as INSERT, UPDATE, or DELETE, the application must rollback the failed transaction and resubmit the transaction.
E: In PRECONNECT failover, the application simultaneously connects to both a primary and a backup node. This offers faster failover, because a pre-spawned connection is ready to use. But the extra connection adds everyday overhead by duplicating connections.
Question No : 15
You plan to create a three-instance RAC database stored in ASM, with its data files in the DATA disk group.
Identify three supported storage solutions for the Fast Recovery Area (FRA).
There are special considerations for choosing a location for the flash recovery area in a RAC environment. The location must be on a cluster file system, ASM or a shared directory configured through NFS. The location and disk quota must be the same on all instances.