Oracle 1z0-076 Dumps

Far Sync instances are a feature of Oracle Data Guard designed to support zero data loss protection over long distances:

• The Data Guard Broker must be used to deploy and manage Far Sync instances (A): Data Guard Broker simplifies the deployment and management of Far Sync instances, which are an integral part of zero data loss protection configurations.
• They enable standby databases to be configured at remote distances from the primary without impacting performance on the primary (C): Far Sync instances are designed to receive redo from the primary database and then forward it to a remote standby database, thereby avoiding any performance impact on the primary database itself.
• A primary database can ship redo directly to multiple Far Sync instances (E): A primary database can be configured to send redo logs to more than one Far Sync instance, which can then forward the redo to their respective remote standby databases.References:
• Oracle Data Guard Concepts and Administration Guide
• Oracle Database High Availability Overview

To increase the number of applier processes on a logical standby database, the following changes can be made:

• C: Increasing the value for the MAX_SERVERS SQL apply parameter would allow for more applier processes to be initiated, assuming that system resources permit.
• D: Increasing the PARALLEL_MAX_SERVERS initialization parameter would allow for more parallel execution processes, which can be used by SQL apply to increase the number of applier processes.

Option A is incorrect as decreasing the number of archiver processes will not necessarily increase the number of applier processes; these are unrelated components.

Option B is incorrect because the 'FREPARER' processes do not exist, it seems to be a typographical error, and the 'REPARER' is not a valid Oracle process or parameter.

Option E is incorrect because the RECOVERY_PARALLELISM parameter controls the number of processes used for instance recovery and media recovery, not for SQL apply.

References: Oracle Data Guard Concepts and Administration guide details the configuration and tuning of SQL apply-related parameters in logical standby databases.

When a physical standby database is opened in real-time query mode, which may be referred to as real-time apply when using Active Data Guard, certain operations can disrupt ongoing sessions. However, with features like Application Continuity and the proper configuration of initialization parameters such as STANDBY_DB_PRESERVE_STATES, user sessions and current buffers may be preserved during role transitions such as a switchover or failover. Specifically, the STANDBY_DB_PRESERVE_STATES parameter can be set to preserve none, all, or only user sessions during such transitions. This ensures that in-flight transactions are not lost and that users do not experience disruptions during the role transitions of a physical standby database​​​​.

References

• Oracle Data Guard Concepts and Administration​​
• Oracle Database Licensing Information User Manual​​
• Oracle Data Guard Broker User Manual​

The ORA-03172: STANDBY_MAX_DATA_DELAY error indicates that the real-time query on the physical standby database is experiencing delays beyond the specified maximum data delay threshold. Increasing the network bandwidth (Option E) can enhance the speed at which redo data is transferred from the primary to the standby database, thereby reducing the likelihood of exceeding the STANDBY_MAX_DATA_DELAY threshold. Reducing I/O latency on the primary database's storage (Option B) ensures that redo data is generated and shipped more efficiently, further mitigating the risk of delay. These actions, focused on optimizing data transfer and processing speed, address the root causes of the ORA-03172 error in a synchronous Data Guard configuration operating in Maximum Availability mode.

D. The database role indicated by FS_FAILOVER_STATUS as BYSTANDER implies that the database is a standby database in the Data Guard configuration. This means the database is neither a primary database nor an active failover target.

E. Since the FS_FAILOVER_OBSERVER_HOST column shows cats, it suggests that this is the host on which the observer would run. However, because the FS_FAILOVER_OBSERVER_PRESENT column is not shown, we cannot definitively state if the observer is currently connected or not. If FS_FAILOVER_OBSERVER_PRESENT is 'YES', the observer is connected, if 'NO', then it's not. In the absence of this column's output, the best assumption based on the available data is that the observer is not connected.

The output shows that the FS_FAILOVER_STATUS is BYSTANDER, which indicates that the database in question is not actively involved in a fast-start failover configuration as a primary or standby. It is in a bystander role, meaning that while it is part of a Data Guard configuration, it is neither a target for failover nor actively participating in failover operations. Additionally, FS_FAILOVER_OBSERVER_HOST shows 'cats', which indicates the host where the observer process is expected to run. However, since there is no information about the observer being present, we can infer that although 'cats' is designated for the observer to run, the observer is not currently connected to this database.

ReferencesOracle documentation on Data Guard configurations and the V$DATABASE view which provides information about the fast-start failover status and observer host.

Data Guard Broker is a management tool that simplifies the configuration, management, and monitoring of Data Guard environments. The prerequisites for using Data Guard Broker include:

• The primary and standby databases must run the same version of the Oracle Database server (A): This ensures compatibility between the primary and standby databases and enables seamless role transitions and data synchronization.
• Network connectivity to the primary database instance must be defined on the servers hosting the standby database instances (B): Proper network connectivity is essential for communication between the primary and standby databases, allowing for the replication of data and the synchronization of changes.
• If any database in the configuration is a RAC database, then the broker configuration files must reside in shared storage accessible by all database instances for all databases in the broker configuration (D): In Real Application Clusters (RAC) environments, shared storage ensures that all instances of the RAC database can access the broker configuration files, facilitating the management of the Data Guard environment across all instances.References:
• Oracle Data Guard Broker documentation
• Oracle Real Application Clusters Administration and Deployment Guide

Flashback Database is a feature that allows reverting a database to a previous point in time, which is extremely useful in various Data Guard configurations:

• It may be used to flash back a physical standby that receives redo from a far sync instance (C): Flashback Database can be used on a physical standby database to revert it to a past point in time, even when it is receiving redo data from a far sync instance. This can be particularly useful to recover from logical corruptions or unwanted changes.
• You can use it when real-time apply is enabled in case the physical standby suffers from logical corruption (D): Even when real-time apply is enabled, which allows redo data to be applied to the standby database as soon as it is received, Flashback Database can be used to revert the physical standby database to a point in time before the logical corruption occurred.
• It may not be used to flash back a primary database after a failover to a physical standby (E): After a failover has occurred from a primary to a physical standby database, making the standby the new primary, Flashback Database cannot be used to revert the old primary database to a state before the failover because the failover operation makes irreversible changes to the database role and configuration.References:
• Oracle Database Backup and Recovery User's Guide
• Oracle Data Guard Concepts and Administration

C. The LGWR (Log Writer) process is responsible for writing redo entries from the redo log buffer to the online redo log files on the primary database. This is a fundamental process in the Oracle Database architecture, ensuring that all changes made to the database are captured for purposes such as recovery, replication, and high availability.

D. Real-time apply on a logical standby database requires standby redo log files. The standby redo log files are used to store redo data received from the primary database before it is applied to the logical standby database. This enables the logical standby to apply changes as they are received, without waiting for the current redo log file to be archived.

E. Similarly, on a physical standby database, standby redo log files are used for real-time apply. They store redo data from the primary database, allowing the physical standby to apply redo data concurrently as it is received, rather than waiting for redo log files to be archived. This capability is crucial for maintaining a physical standby database that is closely synchronized with the primary database with minimal lag.

These functionalities are integral to Oracle Data Guard configurations and are not dependent on Oracle Streams or Oracle GoldenGate, which are separate technologies for data replication and integration​​​​.

After a successful failover to the 'cats' database in a Data Guard configuration:

• B: Sheep, being another standby database, would typically remain in the enabled state unless specifically disabled or if there was a configuration issue.
• D: Dogs, which was the primary database prior to failover, will be in a disabled state as part of the failover process. Manual intervention is required to re-establish 'dogs' as a standby database or to return it to the primary role through another role transition.
• E: If the configuration was in Maximum Availability mode before failover, it would remain in this mode after failover, provided all settings were properly configured and no changes were made to the protection mode.

Option A is incorrect because failover does not automatically change the protection mode to Maximum Performance. The protection mode remains as it was prior to the failover unless manually altered.

References: The behavior of Oracle Data Guard during failover and the resulting configuration state is described in the Oracle Data Guard Broker documentation.

According to the requirements stated:

• Zero data loss must be guaranteed despite the loss of any one component: This necessitates synchronous redo transport to at least one standby database (for no data loss).
• The primary database must be protected against a regional disaster: This implies that there must be a standby database in a different region.
• Performance overhead on the primary should be minimized: This suggests that asynchronous transport should be used where possible to reduce the performance impact on the primary.
• Downtime on the primary for any reason must be kept to a minimum: This is indicative of a requirement for a fast failover mechanism, possibly with a fast-start failover (FSFO) and high availability.

Given these requirements, the appropriate option that fulfills all these is:

• Option C, where 'prima' is the primary database, 'fs1' is the Far Sync instance in the primary region, and 'physt' and 'physt2' are physical standby databases in the primary and remote regions, respectively. In this configuration:

This configuration ensures that there is zero data loss even if the primary region is completely lost, maintains performance by limiting the synchronous transport to the local region with a Far Sync instance, and has a remote standby database in a separate region for disaster recovery purposes.

References:

• Oracle Data Guard Concepts and Administration
• Oracle Data Guard Broker documentation

In the context of Oracle Data Guard and container databases (CDBs) managed by Data Guard Broker:

• All broker actions execute at the root container for container databases (D): When using Data Guard Broker to manage a CDB, the actions performed by the broker are executed at the level of the root container. This is because the root container maintains the control and configuration information that applies to the entire CDB, including all of its pluggable databases (PDBs).
• After a role change, the broker opens all Pluggable databases (PDBs) on the new primary (E): Following a role transition such as a switchover or a failover, Data Guard Broker ensures that all PDBs within the CDB of the new primary database are opened, which is essential to resume operations of the PDBs without manual intervention.References:
• Oracle Data Guard Broker documentation
• Oracle Multitenant Administrator's Guide

• Stop the Observer on host1 to ensure that there are no conflicts between the instances of the Observer running on different hosts.
• Update the Data Guard Broker configuration with the new hostname for the Observer. This step is crucial to redirect the Data Guard Broker to communicate with the Observer on the new host.
• Start the Observer on host2 to resume its operations in the new environment.

Disabling and re-enabling Fast-Start Failover (steps 2 and 4) are not strictly necessary for moving the Observer to a new host. These steps would be more relevant if changes to the configuration of Fast-Start Failover itself were required, which is not the case when simply relocating the Observer.

• A fast recovery area must be configured (B): Flashback Database requires a fast recovery area to be set up because flashback logs are stored there. The fast recovery area is a unified storage location for all recovery-related files and activities.
• The database must be in ARCHIVELOG mode (C): Flashback Database operation relies on the ability to archive redo logs. Therefore, the database must be running in ARCHIVELOG mode for Flashback Database to be enabled.

References:

• Oracle Database Backup and Recovery User's Guide
• Oracle Data Guard Concepts and Administration Guide

In a Data Guard environment, offloading backups to a physical standby database has certain requirements:

• A: Once the primary database is registered in an RMAN catalog, the standby database can also be registered. This allows RMAN to manage backups coherently across both databases and leverage the standby database for backup purposes without interfering with the primary database's workload.
• C: Backups of the standby control file taken while connected to the catalog where the database is registered can be used to restore the control file on the primary database. This ensures that backup metadata is consistent across the Data Guard configuration.

Options B and D are incorrect because there is no strict requirement for the order in which the primary and standby databases must be registered in an RMAN catalog. However, it is a common practice to register the primary database first.

References: The Oracle Database Backup and Recovery User's Guide provides detailed procedures on how to manage RMAN backups in a Data Guard environment, including offloading backups to a standby database.

Based on Oracle Database 19c: Data Guard Administration documents, the three measures that can prevent clients from connecting to the wrong database instances during switchovers, failovers, or regular operations in a Data Guard environment are:

• B. The standby database services must be defined statically with the Listeners running on the standby database hosts.
• D. The client applications must use the correct TNS entries when requesting connections to the database instances.
• E. Client TNS entries for the databases use the correct service names for the intended service.
• In an Oracle Data Guard configuration, correctly configuring Oracle Net Services (including TNS entries and listeners) is crucial for ensuring that clients connect to the appropriate database instance, whether it's the primary or standby. Defining services on the standby database and associating them with listeners ensures that client applications can connect to the standby when needed, especially useful in a role transition or when the standby is open for read-only access or real-time query. It's essential that TNS entries used by client applications specify the correct service names that correspond to the intended database roles, such as primary or standby. This setup facilitates seamless connectivity to the appropriate instance based on the role, especially critical during switchovers and failovers when the roles of the databases change.
• References:Oracle's Data Guard concepts and administration guide provides extensive information on configuring network services for Data Guard environments, ensuring that applications connect to the correct database instance based on the current role of the databases in the Data Guard configuration.

A Far Sync instance is a special kind of Oracle Data Guard configuration that allows synchronous redo transport from a primary database to a remote standby database with minimum impact on the primary database's performance. The Far Sync instance receives redo data synchronously from the primary database (A), then ships it asynchronously to the remote standby database, thus extending zero data loss protection over longer distances and higher network latency environments than would be practical with a synchronous standby alone. The Far Sync instance does not apply the redo data; it just receives and ships it (E). A Far Sync instance does not have data files, and it cannot apply redo to stay synchronized with the primary database.

References:Oracle Database High Availability Overview and Oracle Data Guard Concepts and Administration documentation detail the role and configuration of Far Sync instances, including how they contribute to achieving zero data loss disaster recovery over long distances.

To automate the instantiation of a PDB in the standby database after creating a remote clone in the primary database, certain conditions must be met:

• Open PDBI (remote clone source) in Read Only (A): The source PDB from which the clone is created must be open in read-only mode to ensure a consistent state during cloning.
• Set STANDBY_PDB_SOURCE_FILE_DIRECTORY to in the london database (C): This parameter specifies the location on the standby database where the files from the source PDB should be placed.
• Set STANDBY_FILE_MANAGEMENT to auto in the london database (F): This parameter automates the management of file changes on the standby database when structural changes occur on the primary database, ensuring that the clone operation is reflected automatically on the standby.References:
• Oracle Multitenant Administrator's Guide
• Oracle Data Guard Broker documentation

The DBMS_ROLLING package facilitates a rolling upgrade process across a Data Guard configuration. The START PLAN procedure in particular handles several critical actions, including:

• Creating a guaranteed restore point on the standby databases (B): This ensures that the standby databases can be reverted to their state before the rolling upgrade process in case of any issues.
• Building a LogMiner dictionary on the primary database instance (C): This is necessary for logical standby databases to interpret redo data during the SQL Apply process.
• Creating a guaranteed restore point on the primary database (D): Similar to the standby databases, this ensures that the primary database can be reverted to a known good state if necessary.References:
• Oracle Database PL/SQL Packages and Types Reference
• Oracle Data Guard Concepts and Administration Guide

Creating a physical standby database using RMAN active database duplication requires certain prerequisites to ensure a successful and seamless operation:

• Configure Oracle Net connectivity on the primary host to the standby database instance (A): Proper Oracle Net connectivity between the primary and standby servers is essential for communication and data transfer during the duplication process. Oracle Net services provide the network foundation for Oracle Database, Oracle Net Listener, and Oracle applications.
• Establish user equivalence for the database software owner between the primary host and standby host (B): User equivalence ensures that the user who owns the Oracle Database software on the primary server has the same privileges on the standby server. This is crucial for RMAN to perform operations on both servers without encountering permission issues.
• Startup nomount the standby database instance (C): The standby database instance needs to be started in the NOMOUNT stage before the duplication can begin. This prepares the environment for creating the control file and restoring the database without mounting it, which is a necessary step in the RMAN duplication process.References:
• Oracle Database Backup and Recovery User's Guide
• Oracle Data Guard Concepts and Administration

Transaction Guard provides benefits in terms of transaction consistency and recovery in a Data Guard environment:

• It provides application continuity by rolling back uncommitted transactions interrupted by a failover or switchover (B): Transaction Guard ensures that any uncommitted transactions at the time of an outage are rolled back consistently, thus preserving the integrity of the application's data and state.
• It protects against recoverable errors during a planned or an unplanned outage of a primary database (D): Transaction Guard offers protection against errors that can occur during outages, allowing applications to resume operations more quickly and reliably after recovery.References:
• Oracle Database High Availability Overview
• Oracle Real Application Clusters Administration and Deployment Guide

The RECOVER STANDBY DATABASE FROM SERVICE command in RMAN is designed to automate various steps required to recover the standby database, especially when dealing with an archive gap. When this command is executed, the following actions can occur automatically:

• Remember all data file names on the standby (1): RMAN has the capability to recall the names and paths of all data files associated with the standby database.
• Restart standby in nomount (2): The standby database can be automatically restarted in the NOMOUNT state, allowing recovery operations to proceed without the database being open.
• Restore controlfile from primary (3): RMAN can restore the control file from the primary database to the standby system, ensuring that the standby has the most up-to-date control file.
• Mount standby database (4): After restoring the control file, the standby database is mounted to prepare for data file recovery.
• Rename data files from stored standby names (5): Not typically done automatically by this command.
• Restore new data files to new names (6): New data files added to the primary since the last synchronization can be restored to the standby with their correct names.
• Recover standby (7): Finally, RMAN will apply any necessary redo logs to bring the standby database up to date with the primary.

While some steps, such as renaming data files (5), typically require manual intervention or scripting, most of the recovery process can be handled by RMAN automatically, streamlining the recovery of the standby database.

References:

• Oracle Database Backup and Recovery User's Guide
• Oracle Data Guard Concepts and Administration Guide