DBS-C01 Deployment and Migration Practice Test 20 — 15 Questions

Question 1

A company is migrating a 3 TB SQL Server database to Amazon RDS for SQL Server. The migration must have minimal downtime and support point-in-time recovery after migration. Which THREE steps should be included in the migration plan? (Choose three.)

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

Accepted Answer

Take a full backup of the source database.. A full backup is the foundational step for any SQL Server migration to Amazon RDS. It captures the complete database state at a point in time, which is required for the initial restore into RDS. Without a full backup, you cannot apply differential or transaction log backups to achieve minimal downtime and point-in-time recovery.

Answer

Take a snapshot backup of the source database.

Answer

Take a differential backup.

Question 2

A company is deploying a DynamoDB table for a global application that requires low-latency reads and writes in multiple AWS Regions. Which THREE features should be enabled? (Choose three.)

Accepted Answer

DynamoDB Accelerator (DAX).. DynamoDB Accelerator (DAX) is correct because it provides an in-memory cache for DynamoDB tables, delivering microsecond latency for read-heavy workloads. For a global application requiring low-latency reads across multiple AWS Regions, DAX reduces response times by offloading read traffic from the DynamoDB table to a distributed cache, which is essential for meeting strict performance SLAs.

Answer

DynamoDB Streams.

Answer

Time to Live (TTL).

Question 3

Refer to the exhibit. A developer runs the command against an RDS MySQL instance. The application team reports that the database is experiencing high read latency during peak hours. The database is not currently in Multi-AZ. What is the MOST cost-effective way to reduce read latency?

Accepted Answer

Create a read replica in the same region.. Creating a read replica in the same region offloads read traffic from the primary RDS MySQL instance, reducing read latency during peak hours without incurring the cost of a larger instance or a full Aurora migration. Read replicas are asynchronous and can serve SELECT queries, providing a cost-effective scaling solution for read-heavy workloads.

Answer

Enable Multi-AZ to distribute reads to the standby.

Answer

Upgrade the instance to db.r5.2xlarge.

Answer

Migrate to Aurora MySQL with a read replica.

Question 4

Refer to the exhibit. A developer deploys this CloudFormation template. An application on the EC2 instance cannot connect to the RDS MySQL database. What is the MOST likely cause?

Accepted Answer

The EC2 security group allows inbound MySQL from 0.0.0.0/0 but the RDS security group only allows traffic from the VPC CIDR, which does not include the EC2 security group.. The RDS security group only allows inbound MySQL traffic from the VPC CIDR (e.g., 10.0.0.0/16), but the EC2 instance's security group is not referenced. Since the EC2 instance's private IP may fall outside that CIDR (e.g., if it uses a different subnet or a public IP), the RDS security group blocks the connection. Security group rules must explicitly reference the EC2 security group ID to allow traffic from that specific instance, not just the VPC CIDR.

Answer

The RDS instance has encryption enabled, preventing access from EC2.

Answer

The RDS instance has DeletionProtection enabled, which blocks connections.

Answer

The EC2 instance is in a different Availability Zone than the RDS instance.

Question 5

A company is migrating a 500 GB on-premises Oracle database to Amazon RDS for Oracle. The migration must have minimal downtime. Which AWS service should be used for the initial data load and ongoing replication?

Accepted Answer

AWS Database Migration Service (AWS DMS). AWS Database Migration Service (AWS DMS) is the correct choice because it supports both full-load migration of the initial 500 GB Oracle database and ongoing change data capture (CDC) replication to keep the target RDS for Oracle instance synchronized with minimal downtime. DMS uses Oracle LogMiner or binary reader to capture changes from the source redo logs and apply them continuously, enabling a near-zero downtime migration.

Answer

AWS Snowball Edge for offline data transfer

Answer

Amazon S3 to store backup files and restore

Answer

AWS DataSync

Question 6

A company is moving a self-hosted MySQL database to Amazon Aurora MySQL. The current database uses InnoDB with full-text indexes and triggers. The migration must be done with zero downtime. Which approach meets these requirements?

Accepted Answer

Use AWS DMS with ongoing replication from the source MySQL database. AWS DMS with ongoing replication (change data capture) allows continuous synchronization from the source MySQL database to Amazon Aurora MySQL, enabling a zero-downtime migration. DMS captures incremental changes from the source's binary logs (binlog) and applies them to the target, so the database remains fully operational during the migration. This approach also supports InnoDB tables, full-text indexes, and triggers, as DMS handles schema and data replication for these features. Option C (native MySQL binlog replication) is supported by Aurora MySQL, but it requires an initial seed of data which introduces downtime because the source database typically needs to be in a read-only state for a consistent backup. In contrast, DMS with CDC avoids any initial downtime.

Answer

Use mysqldump to export the database and import into Aurora

Answer

Set up MySQL replication from on-premises to Aurora using native binlog replication

Answer

Export data to Amazon S3 and use Aurora's LOAD DATA FROM S3 command

Question 7

A company wants to migrate a 10 TB Microsoft SQL Server database from on-premises to Amazon RDS for SQL Server. The migration must be completed within a week and minimize network bandwidth usage. Which approach is most suitable?

Accepted Answer

Use AWS Snowball Edge to transfer backup files, then restore to RDS. AWS Snowball Edge is the most suitable approach because it allows you to transfer the 10 TB database backup files physically, bypassing the internet entirely. This eliminates network bandwidth constraints and ensures the migration can be completed within a week, as the data is shipped to AWS and then restored to Amazon RDS for SQL Server using native restore operations.

Answer

Back up the database to Amazon S3 using AWS CLI

Answer

Set up AWS Direct Connect and use DMS

Answer

Use AWS DMS over the internet

Question 8

A company is deploying a new multi-AZ Amazon RDS for PostgreSQL database. The security team requires that all traffic to the database be encrypted in transit. Which configuration ensures this?

Accepted Answer

Enable SSL/TLS and require client connections to use SSL. Enabling SSL/TLS on the RDS instance and requiring client connections to use SSL ensures that all data transmitted between clients and the database is encrypted in transit. This is achieved by setting the rds.force_ssl parameter to 1 in the DB parameter group, which enforces SSL/TLS for all connections, meeting the security team's requirement for encryption in transit.

Answer

Use a customer master key (CMK) for RDS

Answer

Place the RDS instance in a public subnet

Answer

Enable encryption at rest using AWS KMS

Question 9

A company is deploying a MongoDB-compatible database using Amazon DocumentDB. The application requires the ability to perform ad-hoc queries on nested fields within documents. Which DocumentDB feature should be enabled to meet this requirement?

Accepted Answer

Indexes on nested fields. Amazon DocumentDB supports indexing on nested fields, which allows efficient querying of sub-documents and arrays within documents. By creating indexes on specific nested paths (e.g., "address.city"), the query engine can perform index scans instead of full collection scans, enabling fast ad-hoc queries on nested fields. This feature directly meets the requirement for ad-hoc queries on nested fields.

Answer

TTL indexes

Answer

Transactions

Answer

Change streams

Question 10

A company needs to migrate a 2 TB PostgreSQL database from an on-premises data center to Amazon Aurora PostgreSQL. The network bandwidth is limited to 100 Mbps. The migration window is 5 days. Which approach is most cost-effective and likely to succeed?

Accepted Answer

Use AWS DMS with a VPN connection to the on-premises database. AWS DMS with a VPN connection can handle the migration of 2 TB over 100 Mbps within 5 days. At 100 Mbps, the theoretical maximum transfer is about 1.08 TB per day (100 Mbps * 86400 seconds / 8 bits per byte / 1024^3), so 2 TB would take roughly 1.85 days of continuous transfer, well within the 5-day window. DMS supports ongoing replication to minimize downtime, and a VPN is cost-effective compared to Direct Connect for a one-time migration.

Answer

Set up AWS Direct Connect and use DMS

Answer

Use AWS Snowball Edge to transfer data offline

Answer

Export to Amazon S3 and import into Aurora

Question 11

A company is deploying an Amazon RDS for MySQL database in a VPC. The database must be accessible only from a specific set of application servers in the same VPC. Which configuration provides the most secure access?

Accepted Answer

Set the security group inbound rule to reference the security group of the application servers. Referencing the application servers' security group as the source in the RDS inbound rule allows traffic only from those specific instances, regardless of IP changes. This follows the AWS security best practice of using security group IDs for fine-grained, stateful access control within a VPC, eliminating reliance on static IP addresses or CIDR ranges.

Answer

Set the security group inbound rule to allow all traffic from the VPC CIDR

Answer

Place the RDS instance in a separate subnet group

Answer

Set the RDS instance to publicly accessible

Question 12

A company is migrating a 1 TB Oracle database to Amazon RDS for Oracle. The source database has a high volume of small transactions. The migration must minimize source database impact. Which AWS DMS configuration should be used?

Accepted Answer

Use full load only and disable ongoing replication. Using full load only with ongoing replication disabled minimizes source database impact by avoiding the overhead of capturing and applying continuous change data capture (CDC) logs. The high volume of small transactions would otherwise generate a large number of redo log switches and increase I/O on the source, which is contrary to the requirement to minimize impact. A full load only migration transfers a snapshot of the data once, reducing the source load to a single consistent read operation.

Answer

Use batch-optimized apply mode

Answer

Use full load with CDC (ongoing replication)

Answer

Use multiple DMS tasks to parallelize the migration

Question 13

A company is deploying Amazon DynamoDB for a new application. The application requires single-digit millisecond latency for read operations. Which DynamoDB feature should be configured to meet this requirement?

Accepted Answer

DynamoDB Accelerator (DAX). DynamoDB Accelerator (DAX) is an in-memory caching service that sits between your application and DynamoDB, providing microsecond to single-digit millisecond latency for read-heavy workloads. By caching frequently accessed items, DAX offloads read traffic from the underlying DynamoDB tables, ensuring consistent low-latency responses even under high concurrency.

Answer

DynamoDB Streams

Answer

Auto Scaling

Answer

Time to Live (TTL)

Question 14

Which TWO options are valid methods to migrate an on-premises Microsoft SQL Server database to Amazon RDS for SQL Server with minimal downtime? (Choose 2.)

Accepted Answer

Use AWS DMS with ongoing replication. AWS DMS with ongoing replication (change data capture) is a valid method for migrating SQL Server to Amazon RDS with minimal downtime because it allows a full load of the source database followed by continuous replication of incremental changes. This keeps the target database nearly synchronized with the source, enabling a short cutover window. The ongoing replication feature uses SQL Server's transaction logs to capture changes without requiring application downtime.

Answer

Use AWS Snowball Edge

Answer

Use SQL Server Integration Services (SSIS)

Answer

Use AWS Direct Connect

Question 15

Which THREE considerations are important when deploying Amazon Aurora Global Database? (Choose 3.)

Accepted Answer

Each secondary region can have up to 16 read replicas. Amazon Aurora Global Database allows each secondary region to have up to 16 read replicas, enabling low-latency global reads. Option C is correct because a secondary region gets its own Aurora cluster that functions as a cross-region read replica. Option E is correct because replication between the primary and secondary regions typically completes in less than one second, ensuring near-real-time data consistency. Options A and D are incorrect: AWS DMS is not required for Aurora Global Database replication (it uses built-in storage-based replication), and transaction logs are stored in Aurora's storage layer, not in Amazon S3.

Answer

AWS DMS must be used to set up replication

Answer

Amazon S3 is used to store transaction logs