PAS-C01 Migration — Timed 100 Questions

Question 1

A company is migrating a legacy .NET application to AWS. The application uses Windows Authentication and relies on Active Directory for user authentication. The company wants to minimize changes to the application code. Which AWS service should be used to integrate Active Directory with the migrated application?

Accepted Answer

AWS Directory Service for Microsoft Active Directory. AWS Directory Service for Microsoft Active Directory is the correct choice because it provides a fully managed Microsoft Active Directory in the AWS cloud, which natively supports Windows Authentication and Kerberos-based authentication without requiring any code changes. This service allows the migrated .NET application to seamlessly integrate with the existing on-premises Active Directory through a trust relationship or by extending the directory directly into AWS, preserving the application's authentication logic.

Answer

Amazon Cognito

Answer

AD Connector

Answer

Simple AD

Question 2

A company is migrating a 50 TB Oracle database to Amazon RDS for Oracle using AWS DMS. The source database is running on-premises and the network link has a bandwidth of 100 Mbps. The migration must complete within 5 days. What is the MOST effective approach to meet the deadline?

Accepted Answer

Use AWS Snowball to transfer the data offline, then use DMS for CDC. The 50 TB database over a 100 Mbps link would take approximately 48 days for a full load (50 TB * 8 / 100 Mbps / 86400 seconds/day), far exceeding the 5-day deadline. AWS Snowball allows offline transfer of the full database snapshot, bypassing network bandwidth constraints, after which AWS DMS can be used for ongoing change data capture (CDC) to replicate incremental changes. This hybrid approach meets the deadline while ensuring minimal data loss.

Answer

Provision a Direct Connect connection to increase bandwidth

Answer

Use AWS DMS with full load and change data capture (CDC) online

Answer

Use AWS Schema Conversion Tool (SCT) to convert schema, then DMS for data

Question 3

A company is migrating a web application from an on-premises data center to AWS. The application uses a MySQL database that is 500 GB in size. The company wants to minimize downtime during the migration. Which approach should the company use?

Accepted Answer

Use AWS Database Migration Service (DMS) with ongoing replication. AWS Database Migration Service (DMS) with ongoing replication (change data capture, CDC) allows you to perform a live migration with minimal downtime. You can start a full load of the 500 GB MySQL database while the source remains operational, then enable CDC to replicate ongoing changes until you cut over to the target RDS instance, reducing the downtime window to seconds.

Answer

Use an RDS read replica and promote it

Answer

Stop the database, take a mysqldump, and restore to RDS

Answer

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

Question 4

A company is migrating a multi-tier application to AWS. The application includes a load balancer, web servers, and an Oracle database. The migration plan includes using AWS DMS for the database. During the initial full load, the DMS task fails with an error indicating insufficient memory. The source database is on an EC2 instance with 4 GB RAM. What should the migration team do to resolve this issue?

Accepted Answer

Increase the size of the DMS replication instance. Option C is correct because the error 'insufficient memory' during the initial full load in AWS DMS typically indicates that the replication instance does not have enough memory to handle the data volume or LOB processing. Increasing the size of the DMS replication instance provides more memory for caching, transformation, and LOB handling, directly resolving the resource constraint without altering the source database or task structure.

Answer

Disable LOB support in the DMS task

Answer

Split the migration into multiple smaller tasks

Answer

Increase the memory of the source EC2 instance

Question 5

A company is migrating a legacy application to AWS that requires a static IP address for client whitelisting. The application will run on EC2 instances behind an Application Load Balancer (ALB). The company wants to ensure the IP address does not change over time. What should the company do?

Accepted Answer

Use a Network Load Balancer (NLB) with an Elastic IP address. Option D is correct because a Network Load Balancer (NLB) supports static IP addresses by allowing you to assign Elastic IPs directly to each of its Availability Zone subnets. This provides fixed IP endpoints for client whitelisting, while the NLB can forward traffic to the EC2 instances behind an ALB, preserving the application's architecture.

Answer

Assign an Elastic IP to each EC2 instance

Answer

Use Route 53 latency-based routing to point to the ALB

Answer

Use AWS Global Accelerator to get two static IP addresses

Question 6

A company is migrating a 10 TB SQL Server database to Amazon RDS for SQL Server using AWS DMS. The migration is taking longer than expected. Which TWO actions can improve the migration speed? (Choose two.)

Accepted Answer

Enable parallel loading by splitting tables into multiple tasks. Option B is correct because splitting tables into multiple DMS tasks enables parallel loading, which significantly reduces migration time by processing multiple tables concurrently. Option D is correct because increasing the DMS replication instance size provides more CPU and memory resources, allowing the instance to handle larger data volumes and higher throughput more efficiently.

Answer

Use a single DMS task with full LOB mode

Answer

Use S3 multipart upload for the data

Answer

Disable transaction logging on the source

Question 7

A company is planning to migrate a critical application to AWS using the 7 Rs migration strategy. The application is currently running on a large VMware VM. Which THREE strategies are appropriate for this migration? (Choose three.)

Accepted Answer

Rehost: Use AWS VM Import/Export to migrate the VM to EC2. Rehost (A) is appropriate because AWS VM Import/Export allows you to migrate VMware VMs directly to Amazon EC2 as AMIs, enabling a lift-and-shift migration with minimal changes. This is a core 7 Rs strategy for moving existing virtualized workloads to AWS.

Answer

Retire: Decommission the application as it is no longer needed

Answer

Retain: Keep the application on-premises

Question 8

A company is migrating a legacy on-premises application to AWS. The application uses a proprietary database that is not supported by AWS Database Migration Service (DMS). The company needs to minimize downtime and automate the migration as much as possible. Which approach should be used?

Accepted Answer

Use AWS Application Migration Service (MGN) to replicate the entire server, including the database, to AWS.. AWS Application Migration Service (MGN) can replicate entire servers, including the operating system, applications, and the proprietary database, to AWS without requiring database-specific support. This minimizes downtime by using continuous block-level replication and automates the migration by converting the source server into a native AWS instance. Since AWS DMS does not support the proprietary database, MGN provides a viable path for migrating the entire workload as a whole.

Answer

Use AWS Database Migration Service (DMS) with a custom endpoint.

Answer

Export the database as a flat file, upload to Amazon S3, and import into Amazon RDS.

Answer

Use AWS Snowball to transfer database backups, then restore in Amazon RDS.

Question 9

A company is migrating a critical application to AWS using a lift-and-shift strategy. The application has a legacy licensing model tied to specific hardware IDs. The company has already migrated the application to an Amazon EC2 instance but the license validation fails because the hardware ID changed. What is the MOST cost-effective and least disruptive solution?

Accepted Answer

Use AWS License Manager to create a hardware-based license token that matches the original hardware ID.. Option D is correct because AWS License Manager can create a hardware-based license token that binds the license to a specific hardware ID, allowing the application to validate against the original hardware ID even after migration to EC2. This is the most cost-effective and least disruptive solution as it avoids modifying the application code or reverting the migration, and it leverages AWS-native licensing management without requiring dedicated hardware.

Answer

Revert the migration and keep the application on-premises with a VPN connection to AWS for other services.

Answer

Provision a Dedicated Host and associate the instance with it to control hardware IDs.

Answer

Modify the application's license file to accept the new hardware ID.

Question 10

A company is migrating a web application to AWS and wants to use a blue/green deployment strategy to minimize downtime. Which AWS service should be used to route traffic between the blue and green environments?

Accepted Answer

Amazon Route 53. Amazon Route 53 is correct because it supports weighted DNS routing, which allows you to shift traffic gradually between blue and green environments by adjusting the weight values for DNS records. This enables a blue/green deployment strategy with minimal downtime, as Route 53 can route a percentage of traffic to the new environment while keeping the old environment active for rollback.

Answer

Amazon CloudFront

Answer

AWS Global Accelerator

Answer

Application Load Balancer (ALB)

Question 11

An organization is migrating a large data lake (500 TB) from on-premises HDFS to Amazon S3. The migration must be completed within 3 weeks. The network bandwidth between on-premises and AWS is 1 Gbps. What is the MOST efficient migration approach?

Accepted Answer

Use multiple AWS Snowball Edge devices to transfer the data in parallel.. Given the 500 TB data volume and a 3-week deadline, the 1 Gbps network bandwidth yields a theoretical maximum transfer of only ~340 TB in 3 weeks (1 Gbps * 21 days * 86400 seconds / 8 bits per byte), which is insufficient. AWS Snowball Edge devices provide a petabyte-scale, offline data transfer solution that bypasses network constraints entirely, allowing parallel transfers to meet the timeline. This is the most efficient approach because it avoids network bottlenecks and leverages physical shipping for massive datasets.

Answer

Use AWS DataSync over the existing internet connection.

Answer

Order a dedicated AWS Direct Connect circuit at 10 Gbps and use AWS DataSync.

Answer

Use Amazon S3 Transfer Acceleration to speed up the transfer over the internet.

Question 12

A company is migrating a multi-tier application to AWS and wants to ensure high availability. The application has a web tier, application tier, and database tier. The database is currently running on a single on-premises server. Which migration strategy minimizes downtime and provides the HIGHEST availability for the database tier?

Accepted Answer

Use AWS DMS to migrate the database to Amazon RDS Multi-AZ deployment.. Option C is correct because AWS DMS can perform a live migration with minimal downtime by continuously replicating changes from the source database to the target Amazon RDS Multi-AZ deployment. Multi-AZ provides automatic failover to a standby replica in a different Availability Zone, ensuring the highest availability for the database tier. This combination minimizes downtime during migration and provides built-in high availability post-migration.

Answer

Use AWS Database Migration Service (DMS) to migrate to Amazon RDS in a single-AZ deployment, then manually take snapshots.

Answer

Migrate the database to a single large Amazon EC2 instance using AWS Application Migration Service.

Answer

Migrate to Amazon RDS with Multi-AZ deployment and use DMS for initial load.

Question 13

A company is migrating a legacy application to AWS. The application currently uses Oracle Database and the company wants to migrate to Amazon Aurora PostgreSQL with minimal downtime. Which TWO steps should be taken to achieve this? (Choose TWO)

Accepted Answer

Use the AWS Schema Conversion Tool (SCT) to convert the Oracle schema to PostgreSQL.. Option A is correct because the AWS Schema Conversion Tool (SCT) can automatically convert Oracle database schemas (including stored procedures, views, and data types) to a PostgreSQL-compatible format, which is essential when migrating to Amazon Aurora PostgreSQL. Option D is correct because AWS DMS with ongoing replication (change data capture) allows you to keep the source Oracle database and target Aurora PostgreSQL synchronized with minimal downtime, enabling a near-zero-downtime migration by capturing and applying incremental changes.

Answer

Rehost the Oracle database on an Amazon EC2 instance to minimize changes.

Answer

Configure Amazon Aurora PostgreSQL with Multi-AZ for high availability.

Answer

Export Oracle database as dump files and import into Aurora PostgreSQL using native tools.

Question 14

A company is migrating a critical application to AWS using a phased approach. The application uses a custom Linux distribution that is not supported by AWS Application Migration Service. Which THREE steps should the company take to migrate the application? (Choose THREE)

Accepted Answer

Use AWS Server Migration Service (SMS) to replicate the on-premises server to AWS.. AWS Server Migration Service (SMS) is the correct choice because it is an agentless service that can replicate on-premises servers running custom Linux distributions as long as they are supported by the underlying hypervisor. SMS uses incremental replication to create Amazon Machine Images (AMIs) from the source server, enabling a lift-and-shift migration without requiring the application to be converted to a different OS. This approach directly addresses the scenario where AWS Application Migration Service does not support the custom Linux distribution.

Answer

Convert the application to run on Amazon Linux 2 to simplify future management.

Answer

Use AWS Database Migration Service (DMS) to migrate the application server.

Question 15

A company is migrating a legacy on-premises application to AWS. The application requires static IP addresses for its clients to whitelist. The migration strategy includes using an Application Load Balancer (ALB) to distribute traffic across multiple EC2 instances in an Auto Scaling group. The clients require a fixed set of IP addresses to whitelist. Which solution meets the requirement?

Accepted Answer

Use a Network Load Balancer with Elastic IP addresses.. Option C is correct because a Network Load Balancer (NLB) supports static IP addresses via Elastic IP (EIP) assignment per Availability Zone, which allows clients to whitelist a fixed set of IPs. The ALB, by contrast, does not support static IP assignment; its DNS name resolves to dynamic IPs that can change. Using an NLB with EIPs meets the requirement for a fixed whitelist while still distributing traffic to the ALB or directly to EC2 instances.

Answer

Use AWS Global Accelerator with the Application Load Balancer as an endpoint.

Answer

Use an Application Load Balancer and assign Elastic IP addresses to it.

Answer

Launch EC2 instances with Elastic IPs and place them behind a NAT Gateway.

Question 16

A team is migrating an Oracle database to Amazon RDS for MySQL using AWS DMS with ongoing replication (CDC). The initial load succeeded, but the CDC task fails with the error shown in the exhibit. The source Oracle database is on-premises. Which action should the team take to resolve the issue?

Accepted Answer

Connect to the source Oracle database and enable full supplemental logging by executing the command: ALTER DATABASE ADD SUPPLEMENTAL LOG DATA (ALL) COLUMNS;. AWS DMS requires full supplemental logging on the source Oracle database to capture all column values for CDC (ongoing replication). Without it, DMS cannot reconstruct the complete row changes from the redo logs, causing the CDC task to fail. Enabling full supplemental logging with `ALTER DATABASE ADD SUPPLEMENTAL LOG DATA (ALL) COLUMNS;` ensures that every column is logged, allowing DMS to replicate all changes correctly.

Answer

Configure binary logging on the target MySQL RDS instance.

Answer

Stop and restart the DMS task to clear the error.

Answer

Switch the target database to Amazon RDS for Oracle to maintain compatibility.

Question 17

A media company is migrating its on-premises video processing infrastructure to AWS. The current infrastructure uses a custom application that splits video files into segments, transcodes them using FFmpeg, and assembles the final output. The application runs on a single server with 64 vCPUs and 256 GB RAM. The migration plan is to use AWS Batch with EC2 instances for the transcoding jobs. The video files are stored on an on-premises NAS and will be migrated to Amazon S3. The company needs to minimize latency for file access during migration and reduce the time to transfer initial data. The company has a 1 Gbps AWS Direct Connect connection. The total data volume is 500 TB. The migration window is 30 days. Which approach should the team use to transfer the initial data to S3 with the lowest latency and within the migration window?

Accepted Answer

Use multiple AWS Snowball Edge devices to transfer the data in parallel, then copy from the devices to S3 using the Snowball client.. Option B is correct because AWS Snowball Edge devices provide a physical, high-bandwidth transfer method that bypasses network constraints entirely. With 500 TB of data and a 1 Gbps Direct Connect link, the theoretical maximum transfer over the network in 30 days is only ~324 TB (1 Gbps * 30 days * 86400 seconds/day / 8 bits per byte), which is insufficient. Multiple Snowball Edge devices in parallel can transfer the full 500 TB within the migration window without saturating the Direct Connect link, and the Snowball client efficiently copies data to S3 after the devices are returned.

Answer

Use AWS DataSync to transfer data over the Direct Connect connection in multiple concurrent tasks.

Answer

Use a single AWS Snowball Edge device and copy data incrementally.

Answer

Use S3 Transfer Acceleration to speed up transfers over the internet.

Question 18

A company is migrating its on-premises web application to AWS. The application consists of a stateless web tier and a stateful database tier running on a single server. The web tier uses session data stored in the local file system. The database tier runs on MySQL. The company wants to minimize changes to the application code during migration. They plan to use Amazon EC2 for the web server and Amazon RDS for MySQL for the database. After migrating the web server to an EC2 instance and the database to RDS, users report that they are being logged out of the application frequently. What is the most likely cause of this issue?

Accepted Answer

The web server's session data is stored locally and is lost when the EC2 instance is replaced or restarted.. The web tier stores session data in the local file system of the EC2 instance. When the instance is replaced or restarted (e.g., due to Auto Scaling, instance failure, or a maintenance event), that local session data is lost. Since the application code was not modified to use a shared session store (like ElastiCache or DynamoDB), users lose their sessions and are logged out. This is the most likely cause because the migration explicitly minimized code changes and did not address the stateless web tier requirement.

Answer

The RDS instance's backup window is causing database connections to drop.

Answer

The application's session timeout setting was reduced during migration.

Answer

The security group for the web server is blocking inbound session cookies.

Question 19

A company is migrating a legacy on-premises application to AWS. The application uses a MySQL database with a complex stored procedure that runs every hour and takes approximately 10 minutes to complete. The company wants to minimize downtime during migration. Which TWO approaches should the company use to migrate the database?

Accepted Answer

Use AWS Database Migration Service (DMS) with ongoing replication from the source MySQL database to an Amazon RDS for MySQL instance.. Option B is correct because AWS DMS with ongoing replication allows continuous synchronization from the source MySQL database to Amazon RDS for MySQL, minimizing downtime during migration. The complex stored procedure that runs hourly and takes 10 minutes is handled seamlessly as DMS captures ongoing changes, enabling a controlled cutover with minimal disruption.

Answer

Use AWS DMS with a full load only, without ongoing replication, and schedule a cutover window.

Answer

Take a full database dump using mysqldump and import it into an Amazon RDS for MySQL instance during a planned maintenance window.

Answer

Create an Amazon RDS for MySQL read replica from the on-premises database.

Question 20

An administrator is migrating an on-premises application to AWS. The application stores persistent data on a separate disk. The administrator launched an EC2 instance as a test and attached an additional EBS volume for the persistent data. The above exhibit shows the block device mapping for the test instance. Later, the administrator terminates the test instance, but the persistent data must be retained. However, after termination, the persistent data volume is also deleted. What is the most likely cause?

Accepted Answer

The administrator mistakenly stored the persistent data on the root volume (vol-0a1b2c3d4e5f67890), which has DeleteOnTermination set to true.. Option C is correct because the exhibit shows the root volume (vol-0a1b2c3d4e5f67890) as the only volume with DeleteOnTermination set to true. The administrator intended to store persistent data on a separate EBS volume, but the data was actually stored on the root volume. When the instance was terminated, the root volume was deleted due to its DeleteOnTermination flag being true, causing the loss of the persistent data.

Answer

The instance was stopped instead of terminated, and the persistent data volume was detached during the stop.

Answer

The persistent data volume (vol-0f1e2d3c4b5a67890) had DeleteOnTermination set to false, but the administrator inadvertently changed it before termination.

Answer

The persistent data volume was not properly attached to the instance before termination.