DBS-C01 Deployment and Migration Practice Test 2 — 15 Questions

Question 1

A company is migrating a 2 TB MySQL database to Amazon Aurora MySQL. They need to minimize downtime and ensure data consistency. Which approach should be used?

Accepted Answer

Use AWS DMS with ongoing replication (CDC).. AWS DMS with ongoing replication (CDC) is the correct approach because it allows you to perform an initial full load of the 2 TB database while continuously capturing and applying changes from the source MySQL database. This minimizes downtime by keeping the target Aurora MySQL cluster nearly synchronized, and you only need to stop writes briefly during the final cutover to ensure data consistency.

Answer

Use mysqldump to export and import into Aurora.

Answer

Establish AWS Direct Connect and use MySQL replication.

Answer

Use AWS SCT to convert schema and data.

Question 2

A company wants to migrate a self-hosted MongoDB database to Amazon DocumentDB. They need to convert the schema. Which AWS service should they use?

Accepted Answer

AWS Schema Conversion Tool (SCT). AWS Schema Conversion Tool (SCT) is the correct choice because it is specifically designed to convert database schemas from one engine to another, including from MongoDB to Amazon DocumentDB. SCT analyzes the source schema, identifies incompatible objects, and generates a target schema that is compatible with DocumentDB, handling data type mappings, index conversions, and other structural differences.

Answer

AWS Glue

Answer

AWS Database Migration Service (DMS)

Answer

Amazon Athena

Question 3

A company is migrating an on-premises SQL Server database to Amazon RDS for SQL Server. They need to minimize downtime and have a limited network bandwidth of 50 Mbps. The database size is 1 TB. What is the MOST effective approach?

Accepted Answer

Use AWS Snowball Edge to transfer initial load, then DMS for CDC.. The 1 TB database size combined with a 50 Mbps network bandwidth would require over 46 hours for the initial load, making a full network transfer impractical. AWS Snowball Edge allows you to transfer the initial 1 TB seed data offline via a physical appliance, bypassing bandwidth constraints. After the seed is loaded into RDS, AWS DMS with Change Data Capture (CDC) can then replicate ongoing changes over the network, minimizing downtime to only the final cutover window.

Answer

Use AWS DMS with CDC over the network.

Answer

Use AWS SCT to compress data before transfer.

Answer

Use native SQL Server backup and restore to Amazon S3.

Question 4

Which TWO of the following are required when migrating an on-premises Oracle database to Amazon RDS for Oracle using AWS DMS with change data capture (CDC)? (Select TWO.)

Accepted Answer

Use AWS SCT to assess schema compatibility.. Option A (Use AWS SCT to assess schema compatibility) is correct because the AWS Schema Conversion Tool is the standard prerequisite for assessing and converting the source Oracle schema to a form compatible with Amazon RDS for Oracle before DMS migrates the data. Option C (Enable supplemental logging on the source Oracle database) is correct because AWS DMS CDC relies on Oracle redo/archive log mining, which requires supplemental logging (at minimum database-level plus table-level for key columns) to capture change records accurately. Option B is not required because DMS reads directly from the source via log mining and does not need a separate full backup file. Option D is not required because Oracle Data Guard is a high-availability replication feature, not a DMS CDC prerequisite. Option E is not required because AWS DMS can create the target tables automatically during the migration task, so manual creation is optional.

Answer

Create a full backup of the source database.

Answer

Set up Oracle Data Guard for replication.

Answer

Manually create target tables in RDS.

Question 5

Which THREE factors should be considered when choosing between a homogeneous migration and a heterogeneous migration to Amazon RDS? (Select THREE.)

Accepted Answer

Performance requirements of the target database.. Option B is correct because the performance requirements of the target database directly influence whether a homogeneous migration (same engine, e.g., MySQL to Amazon RDS for MySQL) or a heterogeneous migration (different engine, e.g., Oracle to Amazon RDS for PostgreSQL) is appropriate; the target engine's capabilities, such as throughput, IOPS, and concurrency, must meet the workload's demands. Option D is correct because schema compatibility between source and target is a defining consideration: homogeneous migrations preserve schema with minimal transformation, while heterogeneous migrations require schema conversion using AWS SCT and often manual refactoring due to differences in data types, constraints, and indexing. Option E is correct because licensing costs of the target database engine affect the decision, as commercial engines (e.g., Oracle, SQL Server) carry license fees on RDS, whereas open-source engines (e.g., MySQL, PostgreSQL) do not, making heterogeneous migration to an open-source engine potentially more cost-effective. Option A is not a primary factor because network latency between source and target is typically addressed by AWS DMS and network configuration regardless of migration type, and it does not determine homogeneous versus heterogeneous choice. Option C is not a primary factor because application code changes are a consequence of the chosen migration type rather than a deciding factor; they are evaluated after the homogeneous or heterogeneous approach is selected.

Answer

Network latency between source and target.

Answer

Amount of application code changes needed.

Question 6

Which TWO AWS services can be used together to migrate an on-premises MySQL database to Amazon Aurora MySQL with minimal downtime? (Select TWO.)

Accepted Answer

AWS Schema Conversion Tool (SCT). AWS Schema Conversion Tool (SCT) (A) is correct because it converts the source on-premises MySQL schema and code objects into Aurora MySQL-compatible DDL, which is required when the source and target engines differ in features or when schema objects need transformation before migration. AWS Database Migration Service (DMS) (D) is correct because it performs the actual data migration and supports ongoing replication (change data capture) from MySQL to Aurora MySQL, allowing cutover with minimal downtime. Together, SCT handles schema conversion and DMS handles full load plus continuous replication. Amazon Route 53 (B) is a DNS service and does not migrate databases. AWS CloudFormation (C) is an infrastructure-as-code provisioning service, not a data migration tool. AWS Global Accelerator (E) improves network performance and availability but does not perform database schema conversion or data replication.

Answer

Amazon Route 53

Answer

AWS CloudFormation

Answer

AWS Global Accelerator

Question 7

A company is migrating a 2 TB on-premises Oracle database to Amazon RDS for Oracle. The migration must have minimal downtime and support ongoing replication. Which AWS service should be used to accomplish this?

Accepted Answer

AWS Database Migration Service (AWS DMS). AWS DMS is the correct choice because it supports homogeneous migrations (Oracle to Oracle) with minimal downtime through ongoing replication using change data capture (CDC). It can handle a 2 TB database by using a large enough replication instance and enabling task logging for validation, ensuring data consistency during the migration.

Answer

AWS Schema Conversion Tool (AWS SCT)

Answer

AWS DataSync

Answer

AWS Glue

Question 8

A team is deploying a new Amazon Aurora MySQL database and needs to load 5 TB of data from an existing Amazon RDS for MySQL database with minimal downtime. The data is stored in InnoDB tables. Which approach is MOST efficient?

Accepted Answer

Create an Aurora read replica from the RDS for MySQL instance using binlog replication. Creating an Aurora read replica from an RDS for MySQL instance using binlog replication allows the Aurora cluster to synchronize with the source database in near real-time. Once the replica lag reaches zero, you can promote the Aurora cluster to become the primary database, achieving minimal downtime. This approach leverages the native MySQL binlog replication, which is efficient for large datasets like 5 TB and avoids the overhead of exporting or snapshotting the entire database.

Answer

Take a snapshot of the RDS for MySQL instance and restore to Aurora

Answer

Use AWS DMS with full load and ongoing replication

Answer

Use mysqldump to export the database and import into Aurora

Question 9

A company is migrating a 500 GB SQL Server database to Amazon RDS for SQL Server. They need to minimize downtime and support ongoing changes during migration. Which approach should they take?

Accepted Answer

Use AWS DMS with full load and change data capture (CDC). AWS DMS with full load and change data capture (CDC) is the correct approach because it allows the initial 500 GB data load to be migrated while continuously replicating ongoing changes from the source SQL Server database to Amazon RDS for SQL Server. This minimizes downtime by enabling a cutover only after the target is fully synchronized, and it supports ongoing changes during migration without requiring the source database to be taken offline.

Answer

Use native SQL Server backup and restore to RDS

Answer

Set up a Direct Connect connection and use log shipping

Answer

Use SQL Server Integration Services (SSIS) to replicate data

Question 10

A company is deploying a new Amazon RDS for PostgreSQL database. The database will be used by an application that requires read-after-write consistency and low latency. Which deployment configuration is MOST suitable?

Accepted Answer

Deploy as a single-AZ instance with increased instance size. Read replicas in RDS for PostgreSQL use asynchronous replication and do not guarantee read-after-write consistency. For an application requiring read-after-write consistency and low latency, the best choice is to deploy as a single-AZ instance with increased instance size. This avoids replication lag entirely, ensuring that reads from the primary instance always reflect the latest writes, while scaling up provides low latency for both reads and writes.

Answer

Deploy with one or more read replicas in the same region

Answer

Deploy with cross-region replicas

Answer

Deploy as Multi-AZ with a synchronous standby

Question 11

A company is deploying a new Amazon DynamoDB table with global tables for a multi-region application. The application requires strongly consistent reads in the primary region and eventual consistency in secondary regions. Which write strategy should they use?

Accepted Answer

Use DynamoDB global tables with last writer wins (LWW) conflict resolution. DynamoDB global tables use last writer wins (LWW) conflict resolution based on the timestamp in the update, which automatically handles concurrent writes across regions. This strategy satisfies the requirement for strongly consistent reads in the primary region and eventual consistency in secondary regions, as global tables replicate data asynchronously and LWW ensures convergence without additional application logic.

Answer

Use conditional writes to ensure consistency

Answer

Use DynamoDB Streams to replicate writes to secondary regions

Answer

Use DynamoDB transactions across regions

Question 12

A company is deploying a new Amazon DynamoDB table with on-demand capacity. The table will store session data for a web application. Which THREE features should be enabled to improve performance and durability?

Accepted Answer

DynamoDB Accelerator (DAX). DynamoDB Accelerator (DAX) (C) is correct because it is a fully managed, in-memory cache for DynamoDB that delivers microsecond read latency for read-heavy workloads like session lookups, reducing the read load on the table. Point-in-time recovery (PITR) (D) is correct because it provides continuous backups with the ability to restore the table to any second within the last 35 days, which directly improves durability and protects session data against accidental writes or deletes. Global tables (E) are correct because they provide multi-Region, active-active replication, improving durability and availability by keeping copies of the session data in multiple Regions. Auto scaling (A) does not belong because it adjusts provisioned throughput and is unnecessary for an on-demand table, which scales automatically. Time to Live (TTL) (B) does not belong because it only expires and deletes old items to reduce storage cost; it does not improve performance or durability.

Answer

Auto scaling

Answer

Time to Live (TTL)

Question 13

A company is migrating an on-premises PostgreSQL database to Amazon RDS for PostgreSQL. They need to minimize downtime and ensure data consistency. Which TWO methods can be used together to achieve this?

Accepted Answer

Use AWS DMS with full load and CDC. Option C is correct because AWS Database Migration Service (DMS) with a full load plus Change Data Capture (CDC) performs an initial bulk copy of the existing data and then continuously replicates ongoing changes from the on-premises PostgreSQL source to RDS, keeping the target in sync and allowing a cutover with minimal downtime. Option E is correct because pglogical, a logical replication extension for PostgreSQL, can stream incremental changes from the on-premises database to RDS for PostgreSQL, and when combined with an initial data load it maintains consistency while keeping downtime low. Together, DMS CDC or pglogical replication handle the continuous synchronization needed for a minimal-downtime migration. Option A is not appropriate because file system snapshots and EBS copies are for EC2-based storage, not for loading data into RDS, and they don't provide ongoing replication. Option B is not suitable because pg_dump/pg_restore is a one-time logical dump and restore that requires downtime and does not continuously replicate changes. Option D is also unsuitable because exporting to S3 and using COPY is a batch, offline data transfer method that does not keep the target synchronized during the migration.

Answer

Take a file system snapshot and copy to Amazon EBS

Answer

Use pg_dump and pg_restore

Answer

Export data to Amazon S3 and import using COPY

Question 14

A company is migrating a self-hosted MongoDB database to Amazon DocumentDB. They need to ensure that indexes are created after the data load to improve migration performance. Which migration strategy should they use?

Accepted Answer

Use AWS Database Migration Service (DMS) with the 'lob' mode set to 'Don't include LOB columns' and create indexes after the full load.. AWS DMS can be configured to skip LOB columns during the full load, which significantly improves migration performance by reducing data transfer overhead. After the full load completes, indexes can be created on the target DocumentDB database, avoiding the performance penalty of maintaining indexes during the bulk data ingestion. This approach aligns with the requirement to defer index creation until after the data load.

Answer

Use AWS Schema Conversion Tool (SCT) to convert the schema and then load data with DMS.

Answer

Use AWS DMS with 'create indexes before data load' option enabled.

Answer

Use mongodump and mongorestore with the --writeConcern option set to 0.

Question 15

A company is deploying a multi-region application with Amazon Aurora Global Database. They need to ensure that the secondary region can be promoted to primary with minimal data loss in the event of a regional failure. Which configuration should they use?

Accepted Answer

Deploy Amazon Aurora Global Database with one primary Region and up to five secondary Regions.. Amazon Aurora Global Database is designed for low-latency cross-Region replication and provides a managed failover capability that promotes a secondary Region to primary with a Recovery Point Objective (RPO) of typically less than 1 second. This configuration meets the requirement of minimal data loss during a regional failure because replication is done at the storage layer, not through asynchronous binlog replication, ensuring near-zero lag.

Answer

Deploy Amazon Aurora Serverless with cross-Region replication.

Answer

Deploy Amazon RDS for MySQL with cross-Region read replicas.

Answer

Deploy Amazon RDS for PostgreSQL with Multi-AZ and cross-Region snapshot copy.