DBS-C01 Deployment and Migration Practice Test 6 — 15 Questions

Question 1

A company is deploying Amazon RDS for MySQL in a Multi-AZ configuration for high availability. The database must be able to automatically failover to a standby in another Availability Zone. Which RDS feature enables this?

Accepted Answer

Multi-AZ deployment. Option B is correct because Multi-AZ deployments provide automatic failover. Option A is wrong because Read Replicas are for read scaling, not automatic failover. Option C is wrong because Automated backups are for point-in-time recovery, not failover. Option D is wrong because Enhanced Monitoring provides metrics, not failover.

Answer

Automated backups

Answer

Enhanced Monitoring

Answer

Read Replicas

Question 2

A company is deploying a globally distributed application that requires a low-latency, highly available database with multi-region write support. The application needs to handle conflicts automatically. Which AWS database solution meets these requirements?

Accepted Answer

Amazon DynamoDB global tables. Option C is correct because Amazon DynamoDB global tables provide multi-region, multi-master replication with automatic conflict resolution. Option A is wrong because Aurora Global Database supports cross-region replication but only one primary region for writes. Option B is wrong because RDS Multi-AZ is single-region. Option D is wrong because ElastiCache is a caching layer, not a primary database.

Answer

Amazon Aurora Global Database

Answer

Amazon ElastiCache for Redis global datastore

Answer

Amazon RDS Multi-AZ with cross-region read replicas

Question 3

A company is migrating a 500 GB Oracle database to Amazon RDS for Oracle. The migration must complete within a 4-hour downtime window. The network bandwidth is 1 Gbps. Which migration approach minimizes the migration time?

Accepted Answer

Use AWS DMS to perform a full load of the database to RDS.. Option D is correct because AWS DMS can perform a full load plus ongoing replication, but given the bandwidth and data size, using a direct connection (DX) or SCT is not faster. However, the best approach is to use DMS with full load only if replication is not needed; DMS can load data faster than native export/import. Option A is wrong because native export/import is slower and more manual. Option B is wrong because SCT is for schema conversion only. Option C is wrong because DataSync is for files, not databases.

Answer

Use AWS Schema Conversion Tool (SCT) to convert the schema, then use AWS DMS for data migration.

Answer

Use Oracle Data Pump to export and import the database.

Answer

Use AWS DataSync to copy the database files to Amazon S3, then restore to RDS.

Question 4

A company is deploying Amazon RDS for PostgreSQL and needs to ensure that all data at rest is encrypted. Which action should be taken to enable encryption?

Accepted Answer

Specify an AWS KMS key when creating the RDS instance.. Option B is correct because RDS encryption at rest is enabled at instance creation time using AWS KMS. Option A is wrong because encryption is not enabled by default. Option C is wrong because encryption cannot be enabled on an existing unencrypted instance without a snapshot restore. Option D is wrong because you must specify a KMS key.

Answer

Modify the existing RDS instance to enable encryption.

Answer

Enable encryption by default in the RDS console.

Answer

Enable encryption using S3 server-side encryption.

Question 5

A company is migrating a MySQL database to Amazon Aurora MySQL. The database has several stored procedures and triggers. During the migration, some stored procedures fail to execute. What is the most likely cause?

Accepted Answer

The stored procedures use features that are not compatible with Aurora MySQL.. Aurora MySQL is designed to be compatible with MySQL 5.6, 5.7, and 8.0, but it does not support all MySQL features. Stored procedures that rely on deprecated or non-standard MySQL features, such as certain SQL modes, storage engine-specific syntax, or unsupported functions, will fail to execute after migration. This is the most common cause of stored procedure failures during a migration to Aurora MySQL.

Answer

Aurora does not support stored procedures.

Answer

The stored procedures exceed the maximum size limit in Aurora.

Answer

The stored procedures use MyISAM tables, which are not supported by Aurora.

Question 6

A company is migrating a 3 TB SQL Server database to Amazon RDS for SQL Server. The migration must be completed with less than 15 minutes of downtime. The company has set up AWS DMS with ongoing replication. During the final cutover, the DMS task fails with a 'Target error: Cannot insert duplicate key' error. What is the most likely cause?

Accepted Answer

The target table has an identity column that is not set to allow insert of explicit values.. Option D is correct because duplicate key errors in DMS often occur when there are identity columns or triggers on the target that generate values conflicting with the source. Option A is wrong because DMS handles primary key conflicts by default. Option B is wrong because DMS usually handles this if configured, but the error suggests target-side uniqueness. Option C is wrong because transaction log size does not cause duplicate key errors.

Answer

The DMS task is not set to truncate the target before loading.

Answer

The source database transaction log is full.

Answer

The source database has a primary key violation.

Question 7

A company is deploying a new Amazon RDS for MariaDB instance. The database must be accessible from a specific set of EC2 instances in a VPC. How should the company configure security to allow access?

Accepted Answer

Create a security group for the RDS instance that allows inbound traffic from the EC2 instances' security group.. Option C is correct because the RDS security group should allow inbound traffic from the EC2 security group. Option A is wrong because NACLs are stateless and less granular. Option B is wrong because RDS does not support EC2 classic security groups. Option D is wrong because IAM roles are for authentication, not network access.

Answer

Assign the same security group to both the RDS instance and the EC2 instances.

Answer

Attach an IAM role to the EC2 instances that grants access to the RDS database.

Answer

Configure a network ACL to allow inbound traffic from the EC2 instance IPs.

Question 8

A company is migrating an on-premises PostgreSQL database to Amazon RDS for PostgreSQL. The migration must have minimal downtime. Which TWO AWS services should be used together to achieve this?

Accepted Answer

AWS Database Migration Service (AWS DMS). AWS Database Migration Service (AWS DMS) is the correct choice because it is specifically designed for migrating databases to AWS with minimal downtime by using ongoing replication (change data capture, CDC) from the source PostgreSQL database to the target Amazon RDS for PostgreSQL instance. This allows the source database to remain fully operational during the migration, and only a short cutover window is needed to switch applications to the target.

Answer

AWS DataSync

Answer

AWS CloudEndure Migration

Answer

AWS Direct Connect

Question 9

A company is deploying a new Amazon RDS for Oracle instance and needs to ensure high availability and automatic failover. Which TWO configurations should be used?

Accepted Answer

Multi-AZ deployment. Option B (Multi-AZ deployment) is correct because it provisions a synchronous standby replica in a different Availability Zone, enabling automatic failover without data loss when the primary instance fails. This meets the high availability and automatic failover requirements for Amazon RDS for Oracle.

Answer

Read Replicas in a different Region

Answer

Enhanced Monitoring

Answer

Deletion protection

Question 10

A company is migrating a 2 TB Oracle database to Amazon Aurora PostgreSQL. The migration requires ongoing replication for minimal downtime. Which THREE AWS services should be used?

Accepted Answer

AWS Database Migration Service (AWS DMS). Options A, C, and E are correct. AWS DMS performs data migration and ongoing replication, AWS SCT converts the schema, and AWS DMS can use S3 as an intermediate if needed. Option B is wrong because DataSync is for file transfers. Option D is wrong because Lambda is not a migration service.

Answer

AWS DataSync

Answer

AWS Lambda

Question 11

A database administrator is trying to delete the RDS instance named 'prod-critical' using the AWS CLI. The IAM policy shown is attached to the user. What will happen?

Accepted Answer

The delete will fail because the Deny statement explicitly denies the action for that resource.. Option A is correct because the Deny statement explicitly denies the delete action for that specific resource, and Deny always overrides Allow. Option B is wrong because the Allow does not apply to the specific resource due to the Deny. Option C is wrong because the Deny is explicit. Option D is wrong because the Deny is on the action, not condition.

Answer

The delete will succeed only if the user includes a condition.

Answer

The delete will fail because the policy has a syntax error.

Answer

The delete will succeed because the Allow statement grants permission.

Question 12

A developer deploys the CloudFormation stack. After testing, they delete the stack. What happens to the RDS instance?

Accepted Answer

The RDS instance is retained and the stack deletion fails.. Option D is correct because DeletionProtection is set to true, which prevents stack deletion from deleting the RDS instance. Option A is wrong because DeletionProtection prevents deletion. Option B is wrong because the instance is not deleted. Option C is wrong because snapshot is not taken automatically due to DeletionProtection.

Answer

The RDS instance is deleted after a final snapshot is taken.

Answer

The RDS instance is deleted without a final snapshot.

Answer

The RDS instance is retained and a final snapshot is taken automatically.

Question 13

A developer is connecting to an RDS for MySQL instance. What is the endpoint address that should be used in the database connection string?

Accepted Answer

mydb.123456789012.us-east-1.rds.amazonaws.com. Option B is correct because the endpoint address is the DNS name shown in the output. Option A is wrong because the instance ID is not the endpoint. Option C is wrong because the port is not the address. Option D is wrong because the HostedZoneId is not used as the endpoint.

Answer

mydb

Answer

3306

Answer

Z1R2S3V4X5Y6Z7

Question 14

A company wants to migrate an on-premises Oracle database to Amazon RDS for Oracle with minimal downtime. Which AWS service should be used for the initial data load and ongoing replication?

Accepted Answer

AWS Database Migration Service (DMS). AWS DMS can perform a full load and then continuously replicate changes to keep the target in sync with the source, enabling minimal downtime migration. SCT is used for schema conversion, not replication. Direct Connect provides network connectivity, not data migration. Snowball is for offline data transfer and does not support ongoing replication.

Answer

AWS Snowball

Answer

AWS Direct Connect

Answer

AWS Schema Conversion Tool (SCT)

Question 15

A company is deploying a multi-AZ Aurora MySQL database. They need to ensure that failover happens automatically with minimal data loss. Which configuration should be used?

Accepted Answer

Create an Aurora cluster with one primary and two readers in different Availability Zones.. Option C is correct because an Aurora cluster with one primary and two readers in different Availability Zones provides automatic failover with minimal data loss. Aurora uses a shared cluster volume that is replicated six ways across three AZs, ensuring that during a failover, the promoted reader has access to all committed transactions with no data loss. This configuration meets the requirement for multi-AZ high availability and automatic failover within a single region.

Answer

Deploy an Aurora Global Database with a primary in one region and a secondary in another region.

Answer

Use a Multi-AZ RDS for MySQL deployment.

Answer

Configure a single-AZ Aurora instance and enable cross-Region replication.