DBS-C01 Deployment and Migration Practice Test 13 — 15 Questions

Question 1

A company is migrating a 1 TB SQL Server database to Amazon RDS for SQL Server. The migration window is 4 hours. The on-premises network bandwidth is 1 Gbps. The database is not actively used during the migration window. The team wants to minimize migration time and cost. Which migration strategy is most appropriate?

Accepted Answer

Use AWS DMS with full load only.. Option C is correct: using AWS DMS with full load is the fastest and most cost-effective. Option A is wrong because BCP/DTS may be slower. Option B is wrong because native backup/restore requires S3 transfer and is slower. Option D is wrong because Snowball is unnecessary for 1 TB over 1 Gbps.

Answer

Use SQL Server BCP utility to export data and then import using DTS.

Answer

Use AWS Snowball to transfer the database files.

Answer

Create a native backup, upload to S3, restore to RDS.

Question 2

A company is migrating a 3 TB Oracle database from on-premises to Amazon RDS for Oracle. The migration must have zero downtime. The on-premises server uses Oracle Data Guard for disaster recovery. The network bandwidth is 200 Mbps. The team plans to use AWS DMS with CDC from Oracle redo logs. During the initial full load, DMS reports that the source table 'ORDERS' has a table-level supplemental log missing. The migration fails. What should the team do first to resolve this issue?

Accepted Answer

Enable supplemental logging on the Oracle source database for the 'ORDERS' table.. Option B is correct: the missing supplemental log prevents DMS from capturing changes. Option A is wrong because re-creating the task without fixing the log will fail again. Option C is wrong because using a different tool may not address the root cause. Option D is wrong because disabling CDC would cause downtime.

Answer

Switch to Oracle GoldenGate for migration.

Answer

Use AWS SCT to convert the schema and then use a native export/import.

Answer

Recreate the DMS task with 'full load only' to bypass CDC.

Question 3

A company has a 100 GB MySQL database on an EC2 instance. They want to migrate to Amazon RDS for MySQL with minimal downtime. They have set up replication from the source to the target using MySQL native replication. After enabling replication, the 'Seconds_Behind_Master' value is increasing. The source database is write-heavy. What should the team do to reduce replication lag?

Accepted Answer

Increase the RDS instance size to a larger instance class.. Option B is correct: using a larger RDS instance class provides more resources to apply changes. Option A is wrong because enabling Multi-AZ does not improve replication performance. Option C is wrong because DMS is not needed. Option D is wrong because tuning the source may help but the target is the bottleneck.

Answer

Tune the source database to reduce write load.

Answer

Enable Multi-AZ on the RDS instance.

Answer

Switch to AWS DMS for migration.

Question 4

A company is migrating a 500 GB PostgreSQL database from on-premises to Amazon Aurora PostgreSQL. The migration must be completed within 6 hours with minimal downtime. The on-premises network bandwidth is 500 Mbps. The team decides to use AWS DMS. During initial full load, DMS reports a 'Target metadata error: cannot write to Aurora' for a specific table. Investigation shows that the table has a trigger that tries to insert into an external web service. What should the team do to resolve this issue?

Accepted Answer

Disable the trigger on the target Aurora database during migration.. Option C is correct: disabling triggers on the target prevents external calls during migration. Option A is wrong because the issue is not about DMS version. Option B is wrong because disabling the trigger on the source does not help. Option D is wrong because increasing instance size does not fix the trigger issue.

Answer

Increase the DMS replication instance size.

Answer

Upgrade the DMS replication instance engine version.

Answer

Disable the trigger on the source database.

Question 5

A company is migrating a 2 TB Oracle database to Amazon RDS for Oracle. The migration requires minimal downtime. They use AWS SCT to convert the schema and AWS DMS for data migration. After the full load, DMS ongoing replication is unable to capture changes because the archived redo logs are being deleted on the source before DMS can read them. The source database has a log retention setting of 2 hours. The team cannot increase the retention due to storage constraints. What should they do?

Accepted Answer

Configure DMS to use an S3 bucket to store archived redo logs.. Option B is correct: using an S3 staging area to store archived logs temporarily gives DMS more time to read them. Option A is wrong because increasing instance size does not affect log retention. Option C is wrong because it would cause data loss. Option D is wrong because changing to full load only would cause downtime.

Answer

Switch to a full load only migration strategy.

Answer

Disable archiving on the source database.

Answer

Increase the DMS replication instance size to improve log reading speed.

Question 6

A company has a 50 GB MariaDB database on an on-premises server. They want to migrate to Amazon RDS for MariaDB. They have a 100 Mbps network connection. The migration window is 2 hours. The database can be offline for up to 30 minutes. Which migration approach is most appropriate?

Accepted Answer

Create a MariaDB dump, transfer to an EC2 instance in the same region, then import to RDS.. Option A is correct: creating a dump and importing is straightforward and can be done within the window. Option B is wrong because DMS may require more setup. Option C is wrong because Snowball is overkill. Option D is wrong because SCT is for schema conversion, not needed here.

Answer

Use AWS DMS with ongoing replication.

Answer

Use AWS Snowball to transfer the database files.

Answer

Use AWS SCT to convert schema and then use DMS.

Question 7

A company wants to migrate a 1 TB MySQL database to Amazon Aurora MySQL with minimal downtime. The database has a high write load. Which TWO options are valid approaches? (Choose two.)

Accepted Answer

Use AWS DMS with full load and ongoing replication.. Options B and D are correct. Option A is not minimal downtime. Option C is incorrect because SCT is for schema conversion, not data migration. Option E is incorrect because Snowball is not minimal downtime (requires downtime for transport).

Answer

Export to flat files, transfer via AWS Snowball, and import.

Answer

Perform a mysqldump and restore to Aurora.

Answer

Use AWS SCT to convert the schema and then use DMS.

Question 8

A company is migrating a 3 TB SQL Server database to Amazon RDS for SQL Server. The migration must have minimal downtime. The current database uses Transparent Data Encryption (TDE). Which TWO steps are necessary to complete the migration? (Choose two.)

Accepted Answer

Export the TDE certificate and private key from the source and import them to the target RDS instance.. Options A and C are correct. TDE requires exporting the certificate to decrypt at the target. DMS CDC requires full supplemental logging. Option B is wrong because SCT is not needed. Option D is wrong because the database must be in full recovery model for CDC. Option E is wrong because using a backup over S3 is possible but does not address TDE or CDC.

Answer

Set the source database recovery model to simple to reduce log size.

Answer

Use native SQL Server backup and restore to S3.

Answer

Use AWS SCT to convert the schema to Amazon Aurora.

Question 9

A company is migrating a 500 GB MySQL database from on-premises to Amazon RDS for MySQL. The database is critical and must have minimal downtime. Which approach should be used to migrate the database with the least downtime?

Accepted Answer

Use AWS Database Migration Service (DMS) with a replication instance to perform a full load and then ongoing replication until cutover.. Option C is correct because AWS Database Migration Service (DMS) with ongoing replication allows migration with minimal downtime by continuously replicating changes from the source to the target until cutover. Option A is wrong because creating a read replica is not possible from on-premises. Option B is wrong because exporting and importing will cause significant downtime. Option D is wrong because changing the master user is unrelated to migration.

Answer

Modify the on-premises database to use a new master user and then use the AWS Schema Conversion Tool to migrate.

Answer

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

Answer

Export the database using mysqldump and import into RDS using mysql command-line tool. Schedule a maintenance window for cutover.

Question 10

A financial services company is migrating a 2 TB Oracle database to Amazon Aurora PostgreSQL. The database uses Oracle-specific features like hierarchical queries and stored procedures. The company wants to minimize manual code changes. Which service should be used to automate schema conversion?

Accepted Answer

AWS Schema Conversion Tool (SCT).. Option B is correct because AWS Schema Conversion Tool (SCT) is designed to convert database schemas from commercial engines like Oracle to open-source engines like PostgreSQL. Option A is wrong because DMS handles data migration but not schema conversion. Option C is wrong because S3 is storage, not conversion. Option D is wrong because Lambda is for serverless compute, not schema conversion.

Answer

AWS Database Migration Service (DMS) with full load and ongoing replication.

Answer

AWS Storage Gateway to cache data on-premises and then sync to S3.

Answer

AWS Lambda to execute custom scripts for schema transformation.

Question 11

A company wants to migrate an on-premises MongoDB database to Amazon DocumentDB. The migration must be performed with minimal downtime and should support live data synchronization. Which AWS service should be used?

Accepted Answer

AWS Database Migration Service (DMS) with ongoing replication.. Option A is correct because AWS DMS supports MongoDB as a source and DocumentDB as a target, and can perform live synchronization. Option B is wrong because Data Pipeline is for data processing, not live migration. Option C is wrong because Glue is for ETL, not ongoing replication. Option D is wrong because S3 is for storage, not data replication.

Answer

AWS Glue with streaming ETL jobs.

Answer

AWS Data Pipeline to schedule periodic data loads.

Answer

AWS S3 with AWS Lambda functions to sync data.

Question 12

A company is using an Amazon RDS for SQL Server database with Multi-AZ deployment. They need to migrate to Amazon RDS for SQL Server in a different AWS region. The database is 1 TB and cannot tolerate more than 15 minutes of downtime. Which strategy minimizes downtime?

Accepted Answer

Set up cross-region replication using native SQL Server log shipping or DMS with ongoing replication, then perform a DNS cutover to the target instance.. Option D is correct because setting up cross-region replication (using native SQL Server log shipping or DMS) allows continuous data sync and a quick DNS cutover. Option A is wrong because a snapshot restore takes time and does not provide ongoing sync. Option B is wrong because creating a read replica across regions is not supported for SQL Server. Option C is wrong because a new instance would require full data load.

Answer

Create a cross-region read replica in the target region and promote it to a standalone instance.

Answer

Take a snapshot of the source RDS instance and restore it in the target region. Then update the application connection string.

Answer

Use AWS DMS to perform a full load to a new RDS instance in the target region. During the final sync, stop the source and resume from the target.

Question 13

A company is migrating a 50 GB PostgreSQL database from on-premises to Amazon RDS for PostgreSQL. The network bandwidth between on-premises and AWS is 50 Mbps. The migration must complete within 24 hours. What is the most efficient way to transfer the initial data?

Accepted Answer

Use AWS Snowball to physically transfer the database backup to AWS, then load into RDS.. Option B is correct because sending a physical device (AWS Snowball) avoids network constraints and is faster for large data over limited bandwidth. Option A is wrong because it would take too long over 50 Mbps (50 GB ~ 2.2 hours under ideal conditions, but actual throughput may be lower and includes overhead). Option C is wrong because S3 is not a direct migration path for databases. Option D is wrong because VPN does not increase bandwidth.

Answer

Use AWS DMS to perform a full load directly over the internet.

Answer

Set up a VPN connection and use AWS DMS with ongoing replication.

Answer

Use pg_dump to export the database and upload to S3 via the internet, then restore into RDS.

Question 14

A company is migrating a 10 GB MySQL database to Amazon RDS for MySQL. They have a 1 Gbps connection to AWS. The migration must be completed in the least amount of time with minimal manual effort. Which tool should be used?

Accepted Answer

AWS Database Migration Service (DMS).. Option A is correct because AWS DMS is a fully managed service that can migrate data efficiently with minimal manual effort. Option B is wrong because mysqldump requires manual steps and downtime. Option C is wrong because SCT is for schema conversion, not data migration. Option D is wrong because Snowball is overkill for 10 GB.

Answer

AWS Schema Conversion Tool (SCT).

Answer

AWS Snowball Edge.

Answer

mysqldump and mysql command-line tools.

Question 15

A company is migrating an on-premises Oracle database to Amazon Aurora PostgreSQL. They used AWS SCT to convert the schema, but some stored procedures failed to convert automatically. What is the best course of action?

Accepted Answer

Manually rewrite the unconverted stored procedures to PostgreSQL-compatible code based on SCT's assessment report.. Option C is correct because manual remediation of unconverted code is often necessary, and SCT provides an assessment report to guide this. Option A is wrong because DMS does not convert stored procedures. Option B is wrong because PostgreSQL has its own procedural languages. Option D is wrong because Lambda is not designed for schema conversion.

Answer

Use AWS Lambda to automatically convert the stored procedures.

Answer

Use AWS DMS to replicate the Oracle stored procedures as-is to Aurora.

Answer

Switch to Amazon RDS for Oracle to avoid conversion issues.