DBS-C01 Deployment and Migration Practice Test 22 — 15 Questions

Question 1

A company is deploying a new application that requires a MySQL-compatible database with automatic scaling of compute and storage resources. Which AWS service should be used?

Accepted Answer

Amazon Aurora MySQL. Amazon Aurora MySQL is the correct choice because it is a MySQL-compatible relational database that automatically scales compute (up to 128 vCPUs and 244 GiB of memory) and storage (up to 128 TiB in 10 GiB increments) without downtime. Aurora's storage subsystem is distributed and self-healing, scaling as data grows, and its compute can be scaled via Auto Scaling policies or by modifying the instance class with minimal disruption.

Answer

Amazon RDS for MySQL

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Amazon DynamoDB

Answer

Amazon Redshift

Question 2

A company wants to deploy a globally distributed application with a DynamoDB table that uses optimistic locking. Which DynamoDB feature should be used to implement this?

Accepted Answer

DynamoDB Conditional Writes. Optimistic locking in DynamoDB is implemented using conditional writes, specifically the `ConditionExpression` parameter in `PutItem`, `UpdateItem`, or `DeleteItem` operations. By checking that a version attribute (e.g., `version = :expected_version`) matches the client's known value before writing, the application can detect and reject concurrent modifications, ensuring data consistency without locking the entire table.

Answer

DynamoDB Streams

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DynamoDB Global Tables

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DynamoDB Transactions

Question 3

A company is migrating a 2 TB MongoDB database to Amazon DocumentDB. Which TWO factors should be considered when planning the migration?

Accepted Answer

Source MongoDB version compatibility with DocumentDB.. Option D is correct because Amazon DocumentDB only supports certain MongoDB API versions (for example, it is compatible with MongoDB 3.6, 4.0, and 5.0 depending on the engine version), so the source MongoDB version must be checked to confirm the migration tools and features will work. Option E is correct because migrating a 2 TB database involves transferring a large volume of data, so available network bandwidth and latency between the source MongoDB and the DocumentDB cluster directly affect migration duration and reliability. Option A is incorrect because DocumentDB does not automatically store backups in Amazon S3; it retains continuous backups within its own storage for a configurable retention period. Option B is incorrect because LDAP is optional for DocumentDB authentication, not required, since it also supports native username/password authentication. Option C is incorrect because DocumentDB does support encryption in transit using TLS.

Answer

DocumentDB stores backups in Amazon S3 automatically.

Answer

DocumentDB requires LDAP for authentication.

Answer

DocumentDB does not support encryption in transit.

Question 4

Refer to the exhibit. A company's production RDS MySQL instance 'mydb' is configured as shown. The application experiences write latency spikes during peak hours. Which action would most effectively reduce write latency?

Accepted Answer

Change the storage type to Provisioned IOPS (io1) and allocate sufficient IOPS.. Changing the storage type to Provisioned IOPS (io1) and allocating sufficient IOPS directly addresses write latency by providing dedicated, consistent I/O performance. This is the most effective action because write latency spikes during peak hours are typically caused by insufficient IOPS on general purpose SSD storage.

Answer

Create a Read Replica in a different region.

Answer

Increase the allocated storage to 1 TB to improve baseline IOPS.

Answer

Enable Multi-AZ deployment to provide a standby instance.

Question 5

A company is migrating a 5 TB Oracle database to Amazon Aurora PostgreSQL. The database has a 4-hour maintenance window weekly. Which migration approach minimizes downtime?

Accepted Answer

Use AWS Database Migration Service (DMS) with change data capture (CDC).. AWS DMS with CDC allows you to perform an initial full load of the 5 TB database and then continuously replicate ongoing changes from the source Oracle database to the target Aurora PostgreSQL. This minimizes downtime because you can keep the source database fully operational during the migration and only perform a brief cutover to switch applications to the new database, well within the 4-hour maintenance window.

Answer

Use Oracle Data Pump to export and pg_restore to import.

Answer

Use AWS Schema Conversion Tool (SCT) to convert schema and then copy data.

Answer

Use AWS DMS full load only and then manually sync.

Question 6

A company wants to migrate a 200 GB SQL Server database to Amazon RDS for SQL Server with minimal downtime. The database is used by a critical application. Which service should be used for the migration?

Accepted Answer

AWS Database Migration Service (DMS).. AWS DMS is the correct choice because it supports ongoing replication (change data capture) from a SQL Server source to an Amazon RDS for SQL Server target, enabling a migration with minimal downtime. DMS can perform a full load of the 200 GB database and then continuously replicate changes until the cutover, which is essential for a critical application that cannot tolerate extended downtime.

Answer

AWS Schema Conversion Tool (SCT).

Answer

SQL Server Import and Export Wizard.

Answer

SQL Server Management Studio (SSMS) backup and restore.

Question 7

A company is deploying a new application with a PostgreSQL database on Amazon RDS. The database must be highly available across two Availability Zones. Which deployment option meets this requirement?

Accepted Answer

Multi-AZ RDS instance.. A Multi-AZ RDS instance automatically provisions and maintains a synchronous standby replica in a different Availability Zone, providing automatic failover for high availability. This ensures the database remains accessible even if the primary AZ fails, meeting the requirement for cross-AZ high availability.

Answer

RDS with a read replica in another AZ.

Answer

Single-AZ RDS instance.

Answer

Amazon Aurora Global Database.

Question 8

A company is migrating a 10 TB Oracle Data Warehouse to Amazon Redshift. The source database runs on premises with limited bandwidth (100 Mbps). The migration must complete within 5 days. Which approach is most cost-effective and meets the timeline?

Accepted Answer

Use AWS Snowball Edge to transfer the initial full load, then AWS DMS for ongoing changes.. The 10 TB dataset over a 100 Mbps link would take approximately 10 days (10 TB * 8 / 100 Mbps / 86400 seconds/day) for a full load, exceeding the 5-day window. AWS Snowball Edge provides a physical, high-bandwidth transfer for the initial full load, bypassing network constraints, and AWS DMS then captures and applies ongoing changes (CDC) to keep the target in sync. This combination is the most cost-effective as it avoids expensive Direct Connect and meets the timeline.

Answer

Use AWS DMS over the internet to migrate data.

Answer

Use AWS Schema Conversion Tool (SCT) to convert and then upload to S3.

Answer

Use AWS DMS with AWS Direct Connect at 1 Gbps.

Question 9

A company is deploying a MySQL database on Amazon RDS and needs to enforce encryption at rest. Which configuration step is required?

Accepted Answer

Select encryption option when creating the RDS instance.. Amazon RDS for MySQL requires encryption at rest to be enabled at instance creation time by selecting the encryption option in the AWS Management Console, CLI, or API. Encryption at rest uses AWS Key Management Service (KMS) to encrypt the underlying storage, automated backups, read replicas, and snapshots. This setting cannot be applied to an existing unencrypted DB instance, so it must be chosen during the initial launch.

Answer

Use a custom DB parameter group with SSL enabled.

Answer

Modify the DB instance to enable encryption after creation.

Answer

Enable SSL/TLS on the RDS instance.

Question 10

A company needs to migrate an on-premises PostgreSQL database to Amazon Aurora PostgreSQL with minimal downtime. Which AWS service should be used for the ongoing replication?

Accepted Answer

AWS Database Migration Service (DMS).. AWS Database Migration Service (DMS) supports ongoing replication (change data capture, CDC) from an on-premises PostgreSQL source to an Amazon Aurora PostgreSQL target using logical replication slots. This allows you to keep the target database synchronized with minimal downtime after the initial full load, making it the correct choice for a migration with minimal downtime.

Answer

AWS Glue.

Answer

AWS Backup.

Answer

AWS Schema Conversion Tool (SCT).

Question 11

A company is migrating a 5 TB Oracle database to Amazon Aurora PostgreSQL. They have a 4-hour maintenance window weekly. Which THREE steps should be taken to minimize downtime? (Choose 3)

Accepted Answer

Use AWS Snowball to transfer the initial data load.. AWS Snowball provides a physical data transfer mechanism that avoids saturating the network for the initial 5 TB load, which could otherwise take days over typical internet connections. This allows the bulk data to be loaded into Amazon S3 and then into Aurora PostgreSQL before the cutover, while AWS DMS with CDC (Option D) captures ongoing changes to keep the target synchronized with the source during the migration window. Option E is correct because the AWS Schema Conversion Tool (SCT) is essential for converting the Oracle schema (including data types, stored procedures, and indexes) to Aurora PostgreSQL-compatible format before data migration begins, ensuring compatibility and reducing downtime during the final sync.

Answer

Create an Aurora read replica for testing.

Answer

Use AWS Direct Connect for network connectivity.

Question 12

Refer to the exhibit. You run the command and get the output shown. The database is an RDS for MySQL instance. You need to connect to it from an EC2 instance in the same VPC. Which connection string should be used?

Accepted Answer

mysql -h mydb.123456789012.us-east-1.rds.amazonaws.com -P 3306 -u admin -p. The command uses the MySQL client (`mysql`) with the correct fully qualified domain name (FQDN) of the RDS instance, which includes the AWS account ID and region, and the default MySQL port 3306. The `-u admin -p` flags specify the master username and prompt for a password, which is the standard way to connect to an RDS for MySQL instance from an EC2 instance in the same VPC.

Answer

psql -h mydb.123456789012.us-east-1.rds.amazonaws.com -p 5432 -U admin

Answer

mysql -h mydb.us-east-1.rds.amazonaws.com -P 3306 -u admin -p

Answer

mysql -h mydb.123456789012.us-east-1.rds.amazonaws.com -P 5432 -u admin -p

Question 13

A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. The database is 2 TB in size and has a high transaction rate. The migration must have minimal downtime and support ongoing replication. Which AWS service should be used for the migration?

Accepted Answer

AWS Database Migration Service (AWS DMS). AWS DMS is the correct service because it supports ongoing replication (change data capture) from an on-premises Oracle source to Amazon RDS for Oracle, enabling a migration with minimal downtime. It can handle a 2 TB database by using a full load followed by continuous replication of transactions, and it supports Oracle-specific features like supplemental logging and LogMiner for CDC.

Answer

AWS Schema Conversion Tool (AWS SCT)

Answer

AWS Direct Connect

Answer

Amazon RDS Read Replica

Question 14

A company is deploying a new application that requires a MySQL-compatible database with automatic scaling of compute and storage resources. Which AWS service should be used?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Deploy a Multi-AZ RDS instance with a standby in a different Availability Zone. Multi-AZ RDS for PostgreSQL provides synchronous replication to a standby instance in a different Availability Zone, ensuring automatic failover with minimal data loss. This configuration meets the requirement for high availability and automatic failover without manual intervention, as the RDS service handles the DNS change and standby promotion.

Answer

Use a read replica in a different Availability Zone

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Deploy the RDS instance in a single Availability Zone with automated backups

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Deploy the RDS instance in a Cross-Region replication configuration

Question 15

A company is deploying a new Amazon RDS for MySQL database. The security team requires that all data at rest be encrypted. What is the simplest way to meet this requirement?

Accepted Answer

Enable encryption at rest when creating the RDS instance using an AWS KMS key. Amazon RDS for MySQL supports encryption at rest using AWS KMS keys, which must be enabled at instance creation time because encryption cannot be added to an existing unencrypted RDS instance. Option C is correct because it describes the simplest and most direct method: enabling encryption at rest during the initial RDS instance creation with an AWS KMS key, which transparently encrypts the underlying storage, automated backups, read replicas, and snapshots.

Answer

Enable encryption using AWS Certificate Manager

Answer

Use client-side encryption in the application

Answer

Enable encryption at rest on the RDS instance after creation