Amazon DBS-C01 Practice Test - Questions Answers, Page 3
List of questions
Question 21
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A company is running an Amazon RDS for PostgeSQL DB instance and wants to migrate it to an Amazon Aurora PostgreSQL DB cluster. The current database is 1 TB in size. The migration needs to have minimal downtime.
What is the FASTEST way to accomplish this?
Explanation:
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Migrating.htmlMigrating data from an RDS PostgreSQL DB instance to an Aurora PostgreSQL DB cluster by using anAurora read replica.
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Migrating.html#AuroraPostgreSQL.Migrating.RDSPostgreSQ
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Migrating.html#AuroraPostgreSQL.Migrating.RDSPostgreSQL.Replica
Question 22
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A Database Specialist is migrating a 2 TB Amazon RDS for Oracle DB instance to an RDS for PostgreSQL DB instance using AWS DMS. The source RDS Oracle DB instance is in a VPC in the useast- 1 Region. The target RDS for PostgreSQL DB instance is in a VPC in the use-west-2 Region.
Where should the AWS DMS replication instance be placed for the MOST optimal performance?
Explanation:
https://docs.aws.amazon.com/dms/latest/userguide/CHAP_ReplicationInstance.VPC.html#CHAP_ReplicationInstance.VPC.Configurations.ScenarioVPCPeer In fact, all the configurations list on above urlprefer the replication instance putting into target vpc region / subnet / az.
https://docs.aws.amazon.com/dms/latest/sbs/CHAP_SQLServer2Aurora.Steps.CreateReplicationInstance.html
Question 23
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The Development team recently executed a database script containing several data definition language (DDL) and data manipulation language (DML) statements on an Amazon Aurora MySQL DB cluster. The release accidentally deleted thousands of rows from an important table and broke some application functionality. This was discovered 4 hours after the release. Upon investigation, a Database Specialist tracked the issue to a DELETE command in the script with an incorrect WHERE clause filtering the wrong set of rows.
The Aurora DB cluster has Backtrack enabled with an 8-hour backtrack window. The Database Administrator also took a manual snapshot of the DB cluster before the release started. The database needs to be returned to the correct state as quickly as possible to resume full application functionality. Data loss must be minimal. How can the Database Specialist accomplish this?
Explanation:
Question 24
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A company is load testing its three-tier production web application deployed with an AWS CloudFormation template on AWS. The Application team is making changes to deploy additional Amazon EC2 and AWS Lambda resources to expand the load testing capacity. A Database Specialist wants to ensure that the changes made by the Application team will not change the Amazon RDS database resources already deployed.
Which combination of steps would allow the Database Specialist to accomplish this? (Choose two.)
Explanation:
https://docs.amazonaws.cn/en_us/AWSCloudFormation/latest/UserGuide/best-practices.html#cfnbest-practices-changesets
Question 25
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A manufacturing company’s website uses an Amazon Aurora PostgreSQL DB cluster.
Which configurations will result in the LEAST application downtime during a failover? (Choose three.)
Explanation:
Question 26
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A company is hosting critical business data in an Amazon Redshift cluster. Due to the sensitive nature of the data, the cluster is encrypted at rest using AWS KMS. As a part of disaster recovery requirements, the company needs to copy the Amazon Redshift snapshots to another Region. Which steps should be taken in the AWS Management Console to meet the disaster recovery requirements?
Explanation:
If you want to enable cross-Region snapshot copy for an AWS KMS–encrypted cluster, you must configure a snapshot copy grant for a root key in the destination AWS Region Source-Region : configure a cross-Region snapshot for an AWS KMS–encrypted cluster In Destination AWS Region : choose the AWS Region to which to copy snapshots.
https://docs.aws.amazon.com/redshift/latest/mgmt/managing-snapshotsconsole.html#xregioncopy-kms-encrypted-snapshot
Question 27
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A company has a production Amazon Aurora Db cluster that serves both online transaction processing (OLTP) transactions and compute-intensive reports. The reports run for 10% of the total cluster uptime while the OLTP transactions run all the time. The company has benchmarked its workload and determined that a six-node Aurora DB cluster is appropriate for the peak workload.
The company is now looking at cutting costs for this DB cluster, but needs to have a sufficient number of nodes in the cluster to support the workload at different times. The workload has not changed since the previous benchmarking exercise.
How can a Database Specialist address these requirements with minimal user involvement?
Explanation:
Question 28
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A company is running a finance application on an Amazon RDS for MySQL DB instance. The application is governed by multiple financial regulatory agencies. The RDS DB instance is set up with security groups to allow access to certain Amazon EC2 servers only. AWS KMS is used for encryption at rest.
Which step will provide additional security?
Explanation:
Reference: https://aws.amazon.com/blogs/database/applying-best-practices-for-securing-sensitivedata-in- amazon-rds/
Question 29
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A company needs a data warehouse solution that keeps data in a consistent, highly structured format. The company requires fast responses for end-user queries when looking at data from the current year, and users must have access to the full 15-year dataset, when needed. This solution also needs to handle a fluctuating number incoming queries. Storage costs for the 100 TB of data must be kept low.
Which solution meets these requirements?
Explanation:
https://docs.aws.amazon.com/redshift/latest/dg/concurrency-scaling.html
"With the Concurrency Scaling feature, you can support virtually unlimited concurrent users and concurrent queries, with consistently fast query performance. When concurrency scaling is enabled, Amazon Redshift automatically adds additional cluster capacity when you need it to process an increase in concurrent read queries. Write operations continue as normal on your main cluster. User salways see the most current data, whether the queries run on the main cluster or on a concurrency scaling cluster. You're charged for concurrency scaling clusters only for the time they're in use. For more information about pricing, see Amazon Redshift pricing. You manage which queries are sent to the concurrency scaling cluster by configuring WLM queues. When you enable concurrency scaling for a queue, eligible queries are sent to the concurrency scaling cluster instead of waiting in line."
Question 30
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A company is running Amazon RDS for MySQL for its workloads. There is downtime when AWS operating system patches are applied during the Amazon RDS-specified maintenance window.
What is the MOST cost-effective action that should be taken to avoid downtime?
Explanation:
https://aws.amazon.com/premiumsupport/knowledge-center/rds-required-maintenance/
To minimize downtime, modify the Amazon RDS DB instance to a Multi-AZ deployment. For Multi-AZ deployments, OS maintenance is applied to the secondary instance first, then the instance fails over, and then the primary instance is updated. The downtime is during failover. For more information, see Maintenance for Multi-AZ Deployments. https://aws.amazon.com/rds/faqs/ The availability benefits of Multi-AZ also extend to planned maintenance. For example, with automated backups, I/O activityis no longer suspended on your primary during your preferred backup window, since backups are taken from the standby. In the case of patching or DB instance class scaling, these operations occur first on the standby, prior to automatic fail over. As a result, your availability impact is limited to the time required for automatic failover to complete.
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