DBS-C01 Deployment and Migration Practice Test 3 — 15 Questions

Question 1

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

Accepted Answer

Use AWS Database Migration Service (DMS) with a full load and ongoing replication from a change data capture source.. AWS DMS is the correct choice because it supports both a full load of the 500 GB database and ongoing replication using change data capture (CDC) from the on-premises MySQL source. This enables minimal downtime by keeping the target RDS instance synchronized during the migration window, and it handles schema conversion automatically for MySQL-to-MySQL migrations without needing a separate tool.

Answer

Use mysqldump to export the database and import to RDS during a maintenance window.

Answer

Use AWS Schema Conversion Tool (SCT) to convert the schema and migrate data.

Answer

Take a physical backup, copy it to Amazon S3, and restore to RDS.

Question 2

A company is planning to migrate a 2 TB Oracle database to Amazon Aurora PostgreSQL. The database contains large objects (LOBs) and uses stored procedures. Which TWO steps should the company take as part of the migration? (Choose two.)

Accepted Answer

Use AWS Schema Conversion Tool (SCT) to convert the Oracle schema and stored procedures to PostgreSQL-compatible format.. The AWS Schema Conversion Tool (SCT) is specifically designed to convert Oracle schema objects, including stored procedures, to PostgreSQL-compatible format. Since the migration involves stored procedures, SCT is necessary to handle the syntax and logic differences between Oracle PL/SQL and PostgreSQL PL/pgSQL, ensuring the target database schema is ready for migration.

Answer

Set up AWS DMS ongoing replication to keep the target in sync after migration.

Answer

Use AWS DMS native Oracle to PostgreSQL endpoint to migrate data without schema conversion.

Answer

Enable RDS Proxy to reduce connection overhead during migration.

Question 3

Arrange the steps to enable automated backups for an Amazon RDS for PostgreSQL DB instance in the correct order.

Accepted Answer

Modify the DB instance → Set backup retention period to a value greater than 0 → Apply the changes immediately → Confirm the modification. Automated backups are enabled by adjusting the backup retention period in the instance settings and applying the change.

Answer

Set backup retention period to a value greater than 0 → Modify the DB instance → Apply the changes immediately → Confirm the modification

Answer

Modify the DB instance → Apply the changes immediately → Set backup retention period to a value greater than 0 → Confirm the modification

Answer

Confirm the modification → Modify the DB instance → Set backup retention period to a value greater than 0 → Apply the changes immediately

Question 4

Arrange the steps to configure a read replica for an Amazon RDS for PostgreSQL DB instance in a different AWS Region in the correct order.

Accepted Answer

Enable automatic backups on the source DB instance, then create a cross-Region read replica in the target Region, then monitor replication lag.. Cross-Region read replicas require backups enabled on the source, then creating a replica in another Region and monitoring lag.

Answer

Create a cross-Region read replica in the target Region, then enable automatic backups on the source DB instance, then monitor replication lag.

Answer

Monitor replication lag, then enable automatic backups on the source DB instance, then create a cross-Region read replica in the target Region.

Answer

Enable automatic backups on the source DB instance, then monitor replication lag, then create a cross-Region read replica in the target Region.

Question 5

Match each database engine to its default port number.

Accepted Answer

MySQL: 3306. The default ports are: MySQL on 3306, PostgreSQL on 5432, Oracle on 1521, and SQL Server on 1433. Common confusions include swapping MySQL and PostgreSQL ports.

Answer

MySQL: 5432

Answer

PostgreSQL: 3306

Question 6

Match each AWS security feature to its purpose for databases.

Accepted Answer

AWS KMS: Encrypts data at rest and manages encryption keys. AWS KMS handles encryption keys, IAM controls access, Security Groups provide network firewall, and Secrets Manager manages credentials. Common confusions include mixing up KMS with IAM for key management vs. access control.

Answer

AWS KMS: Controls user access to resources

Answer

AWS IAM: Encrypts data at rest using keys

Question 7

A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. The database has a large table with a BLOB column storing PDF files. Which migration approach minimizes downtime?

Accepted Answer

Use AWS Database Migration Service (DMS) with ongoing replication.. AWS DMS with ongoing replication (change data capture) allows you to perform an initial full load of the database while continuously capturing and applying changes from the source Oracle database to the target RDS for Oracle instance. This minimizes downtime because you can cut over to the new database after the initial load and replication lag is near zero, rather than taking the source offline for the entire migration.

Answer

Use Oracle Data Pump to export the table and import into RDS.

Answer

Use Oracle RMAN to back up the database and restore to RDS.

Answer

Export the table without the BLOB column, then import the BLOBs separately.

Question 8

A company wants to migrate a 2 TB PostgreSQL database from on-premises to Amazon Aurora PostgreSQL. The database has high write throughput and the migration must have minimal impact on source performance. Which solution is MOST appropriate?

Accepted Answer

Use pglogical to set up logical replication from the source to Aurora.. Pglogical is a PostgreSQL extension that provides logical replication with minimal overhead on the source, making it ideal for high-write-throughput databases. It allows selective table replication and does not require physical changes to the source, thus avoiding performance impact. AWS DMS (Option B) can also perform ongoing replication but introduces additional overhead and complexity, and it is not as tightly integrated with PostgreSQL's native replication mechanisms as pglogical.

Answer

Create a read replica of the on-premises database and promote it to Aurora.

Answer

Use AWS DMS with ongoing replication from the source to Aurora.

Answer

Set up native PostgreSQL streaming replication from on-premises to Aurora.

Question 9

A company is migrating an on-premises MySQL database to Amazon RDS for MySQL. The database uses InnoDB tables and is 500 GB in size. The migration must be completed within a 2-hour maintenance window. Which approach is MOST likely to meet the requirement?

Accepted Answer

Use mysqldump to export the database and then import it into RDS.. B is correct because mysqldump creates a logical backup that can be imported into Amazon RDS for MySQL within the 2-hour window for a 500 GB database, assuming sufficient network bandwidth and parallel import optimizations. The migration must complete within a fixed maintenance window, and mysqldump allows direct control over the export and import process, making it predictable for a single-shot migration.

Answer

Create a read replica of the on-premises database and promote it to RDS.

Answer

Use AWS DMS with a full load task.

Answer

Take a physical backup of the data directory and copy it to RDS.

Question 10

A company is migrating a 1 TB SQL Server database from on-premises to Amazon RDS for SQL Server. The database has a large table with a LOB column. The network bandwidth between the on-premises data center and AWS is limited to 50 Mbps. The migration must be completed within a week. Which approach should the company use?

Accepted Answer

Use AWS DMS with compression enabled.. AWS DMS with compression enabled is the correct approach because it can migrate the 1 TB database within the limited 50 Mbps bandwidth by compressing data during transfer, reducing the total data volume. DMS supports ongoing replication and handles LOB columns efficiently, making it suitable for a time-constrained migration. The 50 Mbps link can transfer approximately 1.5 TB in a week (50 Mbps * 604,800 seconds / 8 = ~3.78 TB raw capacity), but compression and overhead make DMS the most reliable choice for this scenario.

Answer

Use BCP to export the LOB table to flat files and then import to RDS.

Answer

Use SQL Server native backup and restore to RDS.

Answer

Create a read replica of the on-premises database and promote it.

Question 11

A company is migrating an on-premises MongoDB database to Amazon DocumentDB. The migration must be online with minimal downtime. The source MongoDB is version 4.0 and uses replica sets. Which tool should the company use?

Accepted Answer

Use AWS DMS with MongoDB as source and DocumentDB as target.. AWS DMS (Database Migration Service) supports continuous replication from MongoDB (including replica sets) to Amazon DocumentDB, enabling an online migration with minimal downtime. DMS uses the MongoDB oplog to capture ongoing changes, ensuring data consistency during the cutover. This is the only option that meets the requirement for an online migration with minimal downtime.

Answer

Use MongoDB Compass to export data and import into DocumentDB.

Answer

Use mongodump and mongorestore.

Answer

Create a read replica of the MongoDB replica set and promote to DocumentDB.

Question 12

A company wants to migrate its on-premises Oracle database to Amazon Aurora PostgreSQL. The company needs to convert the database schema and code from Oracle to PostgreSQL. Which AWS service should they use for schema conversion?

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, stored procedures, functions, and other code objects from one database engine to another, such as Oracle to Amazon Aurora PostgreSQL. It analyzes the source schema and generates a target schema with equivalent PostgreSQL syntax, handling data type mappings, PL/SQL to PL/pgSQL conversion, and other compatibility issues. AWS DMS handles data migration but does not perform schema or code conversion.

Answer

AWS DMS

Answer

AWS Glue

Answer

AWS Database Migration Service

Question 13

A company is migrating a 2 TB Oracle database from on-premises to Amazon RDS for Oracle. The network bandwidth is 100 Mbps. The migration must be completed within 3 days. Which approach is MOST efficient?

Accepted Answer

Use AWS DMS with parallel load and ongoing replication.. AWS DMS with parallel load and ongoing replication is the most efficient approach because it can handle the 2 TB migration within the 3-day window over a 100 Mbps link. At 100 Mbps, the theoretical maximum transfer is about 1.08 TB per day (100 Mbps * 86400 seconds / 8 bits per byte / 1024^4), so 2 TB would take nearly 2 days just for the full load. DMS's parallel load splits the data into multiple tasks, maximizing throughput and reducing the full-load time, while ongoing replication captures changes during the migration, allowing a seamless cutover without downtime.

Answer

Use Oracle RMAN to create a backup and restore to RDS.

Answer

Use Oracle Data Pump with a single export and import.

Answer

Use Oracle GoldenGate for real-time replication.

Question 14

A company is migrating a 500 GB PostgreSQL database from on-premises to Amazon Aurora PostgreSQL. The migration must have a recovery point objective (RPO) of less than 5 minutes and a recovery time objective (RTO) of less than 30 minutes. Which migration strategy should the company use?

Accepted Answer

Use AWS DMS with full load and ongoing replication.. AWS DMS with full load and ongoing replication is the correct strategy because it supports continuous change data capture (CDC) from the on-premises PostgreSQL source to Amazon Aurora PostgreSQL, enabling an RPO of less than 5 minutes. The full load phase migrates the initial 500 GB, and ongoing replication keeps the target synchronized with minimal lag, while Aurora’s automated failover and fast recovery help achieve an RTO under 30 minutes.

Answer

Create a read replica of the on-premises database and promote it.

Answer

Take a full backup using pg_basebackup and restore to Aurora.

Answer

Use pg_dump to export the database and import into Aurora.

Question 15

A company is migrating an on-premises MySQL database to Amazon RDS for MySQL. The company wants to minimize application changes. Which endpoint type should the application use after migration?

Accepted Answer

RDS instance endpoint (DNS name). The RDS instance endpoint (DNS name) is the standard connection endpoint for a single RDS DB instance, which is the target of a direct migration from on-premises MySQL to Amazon RDS for MySQL. This endpoint requires no application changes, as the application simply replaces the old on-premises hostname with the RDS instance DNS name, maintaining the same MySQL protocol and connection logic.

Answer

RDS reader endpoint

Answer

RDS cluster endpoint

Answer

RDS console endpoint