DBS-C01 Deployment and Migration Practice Test 10 — 15 Questions

Question 1

A company is migrating a 500 GB SQL Server database to Amazon RDS for SQL Server. The database has a large number of stored procedures and triggers. The migration must have minimal downtime. Which approach should be used?

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

Accepted Answer

Use AWS Database Migration Service (AWS DMS) with full load and ongoing replication. AWS DMS with full load and ongoing replication enables continuous change data capture (CDC) from the source SQL Server database to Amazon RDS for SQL Server, minimizing downtime by keeping the target synchronized until cutover. This approach handles the stored procedures and triggers natively since both source and target are SQL Server, avoiding schema conversion issues.

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Use AWS Schema Conversion Tool (AWS SCT) to convert the schema and AWS DMS for data migration

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Use AWS S3 to store the data and AWS Glue to transform and load into RDS

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Use native SQL Server backup and restore to Amazon RDS

Question 2

A company is migrating an on-premises PostgreSQL database to Amazon RDS for PostgreSQL. The database is 2 TB and the migration must have minimal downtime. Which TWO AWS services should be used together to accomplish this?

Accepted Answer

AWS Schema Conversion Tool (AWS SCT). AWS Schema Conversion Tool (AWS SCT) is used to convert the source PostgreSQL schema and objects to be compatible with Amazon RDS for PostgreSQL, handling any heterogenous elements. AWS Database Migration Service (AWS DMS) then performs the continuous data replication from the on-premises database to RDS, enabling minimal downtime by keeping the target in sync until a cutover.

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AWS CloudFormation

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AWS DataSync

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AWS CloudEndure Migration

Question 3

A company is deploying a new application on AWS that requires a highly available relational database with automatic failover and read scaling. The database size is 100 GB and the workload is balanced between reads and writes. Which THREE AWS services or features should be used?

Accepted Answer

Multi-AZ deployment. Multi-AZ deployment (Option A) is correct because it provides automatic failover for Amazon RDS by provisioning a synchronous standby replica in a different Availability Zone. If the primary DB instance fails, Amazon RDS automatically fails over to the standby, ensuring high availability without manual intervention. This directly meets the requirement for automatic failover in a relational database scenario.

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DynamoDB Accelerator (DAX)

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Amazon RDS Proxy

Question 4

A company is migrating an on-premises MySQL database to Amazon RDS for MySQL. The database is 500 GB and the migration must have minimal downtime. Which TWO AWS services should be used together to accomplish this?

Accepted Answer

AWS Database Migration Service (AWS DMS). AWS DMS (Option D) is correct because it is purpose-built for migrating databases with minimal downtime by continuously replicating changes from the source to the target using change data capture (CDC). AWS SCT (Option E) is correct because it assesses the source MySQL schema and automatically converts any incompatible objects (e.g., storage engines, functions) to be compatible with Amazon RDS for MySQL, ensuring a smooth migration. Together, they enable a near-zero-downtime migration by first performing a full load via DMS and then applying ongoing CDC replication until cutover.

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AWS App2Container

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AWS CloudFormation

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AWS DataSync

Question 5

A company is migrating a 2 TB Oracle database to Amazon Aurora PostgreSQL using AWS DMS. The migration is taking longer than expected, and the ongoing replication lag is increasing. Which action would MOST likely improve the migration speed?

Accepted Answer

Increase the DMS replication instance size.. Increasing the replication instance size (Option C) directly addresses the root cause of slow migration and increasing replication lag: insufficient compute or network resources on the DMS instance. A larger instance provides more CPU, memory, and network bandwidth, enabling faster full-load processing and more efficient ongoing replication. This is the most effective action when the instance is resource-constrained, which is common with a 2 TB database.

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Enable parallel load on the DMS task.

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Decrease the DMS task's batch size and commit interval.

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Disable the DMS task's logging to reduce overhead.

Question 6

A company is planning to migrate a MongoDB database to Amazon DocumentDB. The database has several sharded collections. Which migration strategy should be used?

Accepted Answer

Use AWS DMS with MongoDB as source and DocumentDB as target, enabling ongoing replication.. AWS DMS supports MongoDB as a source and Amazon DocumentDB as a target, and it can perform ongoing replication (change data capture) to keep the target synchronized with the source during migration. This is essential for sharded MongoDB collections because it minimizes downtime by allowing the source to remain operational while data is migrated and changes are continuously applied.

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Set up MongoDB replica set to replicate directly to DocumentDB.

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Use AWS Schema Conversion Tool (SCT) to convert the schema, then manually migrate data.

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Export data using mongodump and import using mongorestore.

Question 7

A company is migrating a 1 TB SQL Server database to Amazon RDS for SQL Server using backup and restore. The database has high transaction volume. Which backup type should be used to minimize downtime?

Accepted Answer

Perform a full backup, then transaction log backups, and restore the full backup with the last log backup.. A full backup followed by transaction log backups allows point-in-time recovery and minimizes downtime during migration. You restore the full backup to RDS, then apply the latest transaction log backup to capture all changes up to the migration cutover, ensuring data consistency without requiring the database to be offline for the entire duration.

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Perform only transaction log backups and restore them to RDS.

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Perform a differential backup and restore it to RDS.

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Perform a full backup and restore it to RDS.

Question 8

A company is migrating a self-hosted Cassandra cluster to Amazon Keyspaces (for Apache Cassandra). The cluster has 10 nodes and handles 50,000 writes per second. Which migration strategy is MOST efficient?

Accepted Answer

Set up Keyspaces as a new datacenter in the existing Cassandra cluster using native replication.. Setting up Amazon Keyspaces as a new datacenter in the existing Cassandra cluster using native replication allows for a live, zero-downtime migration. Cassandra's native replication protocol handles the 50,000 writes per second incrementally, automatically replicating data from the existing cluster to Keyspaces without requiring an export/import step or additional ETL tools.

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Export data using CQL COPY and import into Keyspaces.

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Use AWS Glue to extract data from Cassandra and write to Keyspaces.

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Use AWS DMS with Cassandra as source and Keyspaces as target.

Question 9

A company wants to deploy a DynamoDB table that requires consistent single-digit millisecond latency regardless of traffic spikes. Which DynamoDB capacity mode should be selected?

Accepted Answer

On-demand capacity mode.. On-demand capacity mode is the correct choice because it automatically scales read and write capacity up and down based on actual traffic, eliminating the need for capacity planning and ensuring consistent single-digit millisecond latency even during unpredictable traffic spikes. This mode is designed for workloads with variable or bursty traffic patterns where latency sensitivity is critical.

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DynamoDB Accelerator (DAX) enabled.

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Provisioned capacity mode with auto scaling.

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Provisioned capacity mode with fixed read/write capacity.

Question 10

A company is migrating a 5 TB PostgreSQL database to Amazon Aurora PostgreSQL. The database has complex stored procedures and triggers. The migration must be completed within a 30-minute downtime window. Which approach would meet the requirement?

Accepted Answer

Use AWS DMS with full load and ongoing replication, then perform a cutover.. AWS DMS with full load and ongoing replication allows you to migrate the 5 TB database with minimal downtime by continuously replicating changes from the source PostgreSQL to the target Aurora PostgreSQL. When you are ready, you perform a cutover, which typically takes only a few minutes, meeting the 30-minute downtime window. The complex stored procedures and triggers are handled because DMS supports ongoing replication for PostgreSQL, capturing DML and DDL changes.

Answer

Use Database Migration Service (DMS) with validation only.

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Use AWS SCT to convert the schema and then use pg_dump/pg_restore.

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Set up an Aurora read replica from the source PostgreSQL.

Question 11

A company is migrating a 200 GB Oracle database to Amazon RDS for Oracle. Which TWO steps should be taken to ensure a successful migration? (Choose two.)

Accepted Answer

Use AWS DMS with full load and ongoing replication.. Option C is correct because AWS Database Migration Service (DMS) supports Oracle-to-Amazon RDS for Oracle migrations with a full load plus change data capture (CDC) for ongoing replication, which minimizes downtime for a 200 GB database. Option E is correct because the AWS Schema Conversion Tool (SCT) should be used to assess the source Oracle schema for compatibility issues and convert any objects that are not natively supported by the target RDS for Oracle engine before the data migration. Option A is not required because TDE encryption on the source is not a prerequisite for migrating to RDS for Oracle, and RDS handles encryption at rest via KMS independently. Option B is incorrect because AWS DMS supports homogeneous migrations such as Oracle to RDS for Oracle, not only heterogeneous ones. Option D is not the best choice here because while Data Pump (expdp/impdp) can be used, it is not one of the two steps specifically called out for ensuring a successful DMS-based migration and does not provide ongoing replication.

Answer

Enable TDE encryption on the source database before migration.

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Use AWS DMS only for heterogeneous migrations; use Oracle Data Pump instead.

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Export the database using expdp and import using impdp.

Question 12

A company is deploying a new MySQL database on Amazon RDS. The database must be highly available and support cross-Region disaster recovery. Which TWO actions should be taken? (Choose two.)

Accepted Answer

Create a cross-region read replica.. Option E is correct because enabling Multi-AZ on an RDS MySQL instance automatically provisions a synchronous standby replica in a different Availability Zone within the same Region, providing automatic failover for high availability. Option D is correct because a cross-Region read replica asynchronously replicates data to another Region, which is the standard RDS mechanism for cross-Region disaster recovery (and can be promoted to a standalone primary during a regional failure). Option A is not required by the scenario; encryption at rest with AWS KMS improves security but does not address high availability or disaster recovery. Option B is invalid because RDS Multi-AZ deployments are scoped to a single Region and cannot span multiple Regions. Option C is not correct because automated backups with a 35-day retention support point-in-time recovery within the Region but do not by themselves provide cross-Region DR.

Answer

Enable encryption at rest using AWS KMS.

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Deploy a Multi-AZ instance in multiple regions.

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Enable automated backups with a retention period of 35 days.

Question 13

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.)

Accepted Answer

Take a full backup of the source database.. Option C is correct because a full backup of the source database is the mandatory baseline for any native SQL Server backup/restore migration, and it is the artifact that is restored into Amazon RDS for SQL Server to seed the target database. Option E is correct because transaction log backups capture all changes made after the full backup, and restoring them (with NORECOVERY) brings the RDS target to the desired point in time, enabling point-in-time recovery and minimizing the data gap before cutover. Option D is correct because AWS DMS can be configured with ongoing replication (change data capture) from the source to the RDS target after the initial restore, keeping the target continuously synchronized so the final cutover requires only minimal downtime. Option A is not appropriate because a snapshot backup is a storage-level/VM-level operation, not a SQL Server native backup that can be restored into RDS for SQL Server, and it does not support the log-chain needed for point-in-time recovery. Option B is not appropriate because a differential backup alone cannot seed a restore chain and is not required when a full backup plus transaction log backups are used for the migration.

Answer

Take a snapshot backup of the source database.

Answer

Take a differential backup.

Question 14

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).. Option E, DynamoDB global tables, is correct because global tables provide multi-Region, active-active replication so the application can read and write with low latency in multiple AWS Regions. Option A, DynamoDB Accelerator (DAX), is correct because DAX is an in-memory cache that delivers microsecond read latency for read-heavy workloads, complementing the global table deployment. Option B, on-demand capacity mode, is correct because it automatically scales read/write capacity to match unpredictable global traffic without manual provisioning, helping maintain low latency during demand spikes. Option C, DynamoDB Streams, is not required here because it captures item-level changes for event processing, not for multi-Region low-latency access. Option D, Time to Live (TTL), is not required because TTL only expires items automatically and does not improve read/write latency or multi-Region performance.

Answer

DynamoDB Streams.

Answer

Time to Live (TTL).

Question 15

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.

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The RDS instance has DeletionProtection enabled, which blocks connections.

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