ANS-C01 Practice Test 3 — 10 Questions

Question 1

A company has a VPC with a CIDR of 172.16.0.0/16. They have a subnet 172.16.1.0/24 for web servers and another subnet 172.16.2.0/24 for database servers. The web servers need to access the database servers on port 3306. Which configuration is required?

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

Accepted Answer

Web SG: outbound to DB SG on port 3306. DB SG: inbound from web SG on port 3306.. Security groups are stateful and control traffic at the instance level. The web server security group needs an outbound rule allowing traffic to the database security group on port 3306, and the database security group needs an inbound rule allowing traffic from the web security group on port 3306. This ensures that only the web servers can initiate connections to the database servers on the required port.

Answer

Configure network ACLs to allow inbound on port 3306 from web subnet.

Answer

Web SG: inbound from 0.0.0.0/0 on port 3306. DB SG: outbound to web SG on port 3306.

Answer

Web SG: outbound to DB SG on all ports. DB SG: inbound from web SG on all ports.

Question 2

A company wants to connect its on-premises data center to AWS using a dedicated, high-bandwidth, low-latency connection. The data center is collocated with an AWS Direct Connect location. Which AWS service should be used to establish this connection?

Accepted Answer

AWS Direct Connect. AWS Direct Connect is the correct service because it provides a dedicated, private, high-bandwidth, low-latency connection from an on-premises data center to AWS. Since the data center is collocated with an AWS Direct Connect location, the company can establish a physical cross-connect directly to the AWS Direct Connect router, bypassing the public internet entirely.

Answer

VPC peering

Answer

AWS Transit Gateway

Answer

AWS Site-to-Site VPN

Question 3

A network engineer has created a gateway VPC endpoint for S3 as shown in the exhibit. The endpoint is associated with route table rtb-12345678. An EC2 instance in a subnet that uses route table rtb-12345678 tries to download an object from my-bucket. The request fails with an access denied error. Which change should the engineer make to resolve the issue?

Accepted Answer

Add a route in route table rtb-12345678 that sends traffic to the S3 service via the VPC endpoint.. The endpoint policy requires the aws:SourceVpc condition to match the VPC ID, but the condition key is misspelled or the value is incorrect? Actually, the condition is correct. However, the error is likely because the route table does not have a route to the endpoint. Gateway endpoints require a route in the associated route table that points to the endpoint. Option A is wrong because the endpoint policy already allows s3:GetObject. Option B is wrong because the endpoint is already associated with the route table. Option C is wrong because the bucket policy is not shown; but the issue is likely the route. Option D is correct: add a route to the S3 service in route table rtb-12345678.

Answer

Associate the endpoint with a different route table.

Answer

Add a bucket policy to my-bucket that allows access from the VPC endpoint.

Answer

Modify the endpoint policy to allow all S3 actions.

Question 4

Which TWO of the following are valid methods to connect an on-premises data center to a VPC in AWS? (Choose 2.)

Accepted Answer

AWS Direct Connect. AWS Direct Connect is a correct answer because it provides a dedicated, private network connection from an on-premises data center to AWS, bypassing the public internet for consistent latency and higher bandwidth. This service uses industry-standard 802.1Q VLANs to create virtual interfaces, enabling direct access to VPCs via private virtual interfaces (VIFs) or transit virtual interfaces for use with Transit Gateway.

Answer

VPC endpoint

Answer

Transit Gateway

Answer

VPC peering

Question 5

A company has a VPC with two subnets: subnet A (10.0.1.0/24) and subnet B (10.0.2.0/24). An EC2 instance in subnet A needs to communicate with an EC2 instance in subnet B. The instances are in the same VPC. What is the default behavior?

Accepted Answer

Communication is allowed by default because they are in the same VPC. By default, all instances within the same VPC can communicate with each other regardless of which subnet they reside in, as long as the VPC's main route table and network ACLs allow the traffic. The VPC's implicit router provides connectivity between all subnets, and the default security group allows inbound traffic from other members of the same security group. Therefore, an EC2 instance in subnet A can communicate with an instance in subnet B without any additional configuration.

Answer

Communication is not allowed by default; a VPC peering connection is required

Answer

Communication is allowed only if they are in the same subnet

Answer

Communication is allowed only if a transit gateway is attached

Question 6

A company is designing a multi-region active-active application. They need to ensure that traffic is routed to the closest healthy region and that failover happens automatically. Which TWO services should be used together to achieve this?

Accepted Answer

AWS Global Accelerator with endpoint groups. AWS Global Accelerator (C) uses Anycast IPs to direct traffic to the closest healthy endpoint group, automatically rerouting traffic if a region becomes unhealthy. This provides fast regional failover and low-latency routing without DNS caching delays, making it ideal for active-active multi-region applications.

Answer

AWS Transit Gateway with inter-region peering

Answer

Amazon CloudFront with multiple origins

Answer

AWS Direct Connect with multiple locations

Question 7

A company has a multi-VPC architecture with VPCs in the same region. They need to ensure that traffic between VPCs never traverses the public internet and is encrypted in transit. Which solution meets these requirements with the lowest operational overhead?

Accepted Answer

Use AWS PrivateLink to connect VPCs via Network Load Balancers.. AWS PrivateLink allows you to connect VPCs privately using VPC endpoints and Network Load Balancers. Traffic stays within the AWS network and never traverses the public internet. When the application uses TLS/HTTPS, the traffic is encrypted end-to-end. This solution has low operational overhead because PrivateLink is fully managed and requires no VPN tunnels or third-party appliances.

Answer

Use AWS Transit Gateway with IPsec VPN attachments between VPCs.

Answer

Use VPC peering connections between all VPCs.

Answer

Use AWS Transit Gateway with VPC attachments and enable multicast.

Question 8

A company is using AWS Site-to-Site VPN connections to connect multiple branch offices to a central VPC. The network team wants to ensure high availability and automatic failover if one VPN tunnel goes down. Which configuration should be implemented?

Accepted Answer

Use the two tunnels provided by the VPN connection with dynamic routing (BGP). Each AWS Site-to-Site VPN connection provides two tunnels for high availability. By using dynamic routing (BGP) with both tunnels, the VPN automatically fails over to the second tunnel if the first goes down, without manual intervention. This meets the requirement for automatic failover and high availability.

Answer

Configure a second VPN connection to the same customer gateway and use BGP with equal-cost multipath

Answer

Use a single tunnel and rely on AWS automatic recovery

Answer

Configure static routes with a higher metric for the secondary tunnel

Question 9

Which TWO services can be used to centrally manage and monitor VPN connections across multiple AWS accounts? (Choose 2.)

Accepted Answer

AWS Network Manager. AWS Network Manager centrally manages and monitors VPN connections across multiple AWS accounts by providing a global view of your network topology, including on-premises and AWS resources. It integrates with Transit Gateway to monitor VPN tunnel status and performance metrics, enabling cross-account visibility via resource shares.

Answer

AWS CloudFormation

Answer

AWS Organizations

Answer

AWS Direct Connect Gateway

Question 10

A company needs to connect its on-premises data center to a VPC in AWS using a dedicated, private, and high-bandwidth connection. Which AWS service should be used?

Accepted Answer

AWS Direct Connect. AWS Direct Connect is the correct choice because it provides a dedicated, private, high-bandwidth network connection from an on-premises data center directly to AWS, bypassing the public internet. This meets the requirements for a private, low-latency, and consistent network path, unlike VPN-based solutions that traverse the internet.

Answer

AWS Client VPN

Answer

VPC Peering

Answer

AWS Site-to-Site VPN