ANS-C01 Practice Test 7 — 10 Questions

Question 1

A company is designing a hybrid network with AWS Direct Connect. They have multiple VPCs in the same Region and want to use a single Direct Connect connection to access all VPCs. Which AWS resource should be used?

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

Accepted Answer

Direct Connect Gateway. A Direct Connect Gateway allows you to associate up to 10 Virtual Private Gateways (VGWs) or Transit Gateways in the same or different AWS accounts, enabling a single Direct Connect connection to reach multiple VPCs in the same Region. This is the correct resource because it acts as a hub that terminates the Direct Connect virtual interfaces (VIFs) and propagates routes to the associated VPCs via their VGWs or Transit Gateways.

Answer

AWS Transit Gateway

Answer

AWS Site-to-Site VPN

Answer

Virtual Private Gateway

Question 2

A company has a VPC with a public subnet and a private subnet. They launch an EC2 instance in the private subnet with a private IP only. The instance needs to download patches from the internet. Which configuration is required?

Accepted Answer

Create a NAT gateway in the public subnet and add a default route to the NAT gateway in the private subnet's route table.. A NAT gateway in the public subnet provides outbound internet access for instances in the private subnet while preventing inbound connections from the internet. By adding a default route (0.0.0.0/0) in the private subnet's route table pointing to the NAT gateway, traffic from the EC2 instance destined for the internet is forwarded to the NAT gateway, which then uses its Elastic IP to communicate with the internet. This allows the instance to download patches without requiring a public IP or direct internet gateway access.

Answer

Launch a NAT instance in the private subnet and configure source/destination check.

Answer

Create a VPC endpoint for the patch service.

Answer

Attach an internet gateway to the VPC and add a default route to it in the private subnet's route table.

Question 3

A company is using AWS Organizations to manage multiple accounts. The security team wants to enforce that all S3 buckets have server-side encryption enabled. Which SCP should be applied to the root OU?

Accepted Answer

Deny s3:PutBucketEncryption unless encryption settings include AES256 or aws:kms. A Service Control Policy (SCP) applied to the root OU can deny the s3:PutBucketEncryption action unless specific encryption settings (AES256 or aws:kms) are used. This prevents any account in the organization from creating or modifying S3 buckets without encryption. Option A is wrong because IAM policies are attached to principals (users/roles), not to OUs, and cannot enforce encryption across all accounts. Option B is wrong because SCPs are applied to OUs or accounts, not to individual resources like S3 buckets. Option D is wrong because AWS Config rules can detect non-compliance but do not enforce via SCPs; they would require an automated remediation action.

Answer

Create an IAM policy that allows s3:PutBucketEncryption only with specific conditions

Answer

Attach an IAM policy to each S3 bucket requiring encryption

Answer

Use AWS Config rules to auto-enable encryption on existing buckets

Question 4

A company wants to audit all changes to security groups in their AWS account. They need to be notified whenever a security group rule is added, modified, or removed. They also want to see who made the change. Which solution should they implement?

Accepted Answer

Enable AWS CloudTrail and create a CloudWatch Events rule that triggers on EC2 SecurityGroup events, sending notifications via SNS.. AWS CloudTrail captures all API calls, including EC2 SecurityGroup-related actions (AuthorizeSecurityGroupIngress, RevokeSecurityGroupIngress, etc.), recording the identity of the caller. A CloudWatch Events rule can filter for these specific events and trigger an SNS notification, providing both the change details and the IAM user or role that made the change. This meets the audit and notification requirements precisely.

Answer

Use AWS Trusted Advisor to check for security group changes and send email alerts.

Answer

Use AWS Config to monitor security group changes and trigger a Lambda function to send notifications.

Answer

Enable VPC Flow Logs and analyze logs for changes to security group rules.

Question 5

A company needs to log all network traffic to and from EC2 instances for security analysis. Which TWO services can capture this data? (Choose 2)

Accepted Answer

VPC Flow Logs. Options B and D are correct. VPC Flow Logs capture metadata (IP addresses, ports, protocols) about network traffic. Traffic Mirroring captures actual packet content for deep packet inspection. Option A (AWS Config) is incorrect because it records configuration changes, not network traffic. Option C (AWS CloudTrail) is incorrect because it logs API calls, not network traffic. Option E (Amazon CloudWatch Logs) is incorrect because it is for log storage and monitoring, not for capturing network traffic.

Answer

AWS Config

Answer

AWS CloudTrail

Answer

Amazon CloudWatch Logs

Question 6

A company is setting up AWS Direct Connect with a 1 Gbps dedicated connection. They want redundant connectivity with automatic failover. What is the most cost-effective way to achieve this?

Accepted Answer

Provision a second Direct Connect connection at a different location and configure BGP.. Achieving true redundancy with automatic failover for AWS Direct Connect requires physically diverse connections. A second Direct Connect connection at a different location, combined with BGP routing (e.g., using AS_PATH prepending or MED for traffic engineering), ensures that traffic automatically fails over if one connection goes down. While a VPN over the internet (option D) might seem cost-effective, it introduces variable latency, potential bandwidth constraints, and additional data transfer costs, making it less suitable for consistent performance and automatic failover in a dedicated connectivity context. Therefore, provisioning a second Direct Connect connection is the most cost-effective approach that meets the requirements.

Answer

Use a single connection with multiple VLANs.

Answer

Use a single connection with a VPN over the same connection for redundancy.

Answer

Provision a single Direct Connect connection and use a VPN over the internet as backup.

Question 7

A company has a VPC with a CIDR of 10.0.0.0/16. They have created a VPC peering connection with another VPC (CIDR 10.1.0.0/16). They want to enable DNS resolution between the VPCs. Which TWO actions must be taken?

Accepted Answer

Both VPCs must have the 'Enable DNS Resolution' attribute set to true in their VPC settings.. To enable DNS resolution across a VPC peering connection, two conditions must be met. First, both VPCs must have the 'Enable DNS Resolution' attribute set to true in their VPC settings, which requires both EnableDnsHostnames and EnableDnsSupport to be enabled (Option B). Second, the VPC peering connection itself must have DNS resolution enabled. This can be done by the accepter when accepting the peering connection or later by modifying the peering connection (Option D). Option A is incorrect because the requester does not accept the peering connection; the accepter does. Option C is not required for DNS resolution. Option E (route table entries) is necessary for connectivity but not specifically for DNS resolution.

Answer

The requester must accept the peering connection with the 'Enable DNS Resolution' option checked.

Answer

Ensure both VPCs are in the same AWS region.

Answer

The route tables must include a route for the peered VPC's CIDR.

Question 8

A company has a VPC with an IPv4 CIDR block of 10.0.0.0/16. They need to add additional IP address space for new subnets. The existing subnets use 10.0.0.0/17 and 10.0.128.0/17. Which CIDR block should be added as a secondary CIDR to the VPC to provide the most additional contiguous address space?

Accepted Answer

10.1.0.0/16. (10.1.0.0/16) is correct because the VPC already uses the entire 10.0.0.0/16 range (split into 10.0.0.0/17 and 10.0.128.0/17). To add contiguous address space, you must use a different /16 block that is adjacent in the private IPv4 address space, such as 10.1.0.0/16. AWS VPCs support secondary CIDRs that must not overlap with existing CIDRs, and 10.1.0.0/16 provides a non-overlapping, contiguous block.

Answer

10.0.0.0/0

Answer

10.0.0.0/8

Answer

10.0.0.0/16

Question 9

A company is using AWS CloudTrail to log API calls. They want to ensure that log files are encrypted at rest and that only authorized users can access them. Which combination of actions should they take?

Accepted Answer

Enable default encryption (SSE-S3) on the S3 bucket and attach a bucket policy that restricts access to authorized IAM principals.. Enabling default encryption (SSE-S3) on the S3 bucket ensures logs are encrypted at rest. Attaching a bucket policy that restricts access to authorized IAM principals ensures only authorized users can access them. This combination fully satisfies both requirements. Option A (SSE-KMS with a customer managed key) encrypts the logs at rest, but it does not include the access controls needed to ensure only authorized users can access the logs—additional measures would be required. Option B (disable public access and enable versioning) does not encrypt the logs. Option D (SSE-C) is impractical for CloudTrail logs because it requires you to supply encryption keys with every API call and does not inherently restrict access. Therefore, option C is the correct combination.

Answer

Use SSE-KMS with a customer managed key and allow CloudTrail to use the key.

Answer

Disable public access to the S3 bucket and enable versioning.

Answer

Enable SSE-C on the S3 bucket and provide the encryption key in each API call.

Question 10

A company is experiencing intermittent connectivity issues between a VPC and an on-premises data center over an AWS Direct Connect connection. The network engineer checks the Direct Connect virtual interface status and sees it is 'up'. However, BGP sessions are flapping. Which action should the engineer take to diagnose the issue?

Accepted Answer

Check the BGP keepalive and hold timers on both sides.. BGP session flapping is often caused by mismatched keepalive or hold timers between the customer router and AWS. Checking and aligning these timers helps diagnose and resolve the flapping. Option A is incorrect because the virtual interface is already up, indicating VLAN configuration is likely correct. Option B is incorrect; BFD is used for faster failure detection, not for diagnosing timer mismatches that cause flapping. Option C is excessive; recreating the virtual interface with a new VLAN ID is unnecessary when the issue is BGP-related.

Answer

Verify the VLAN configuration on the customer router.

Answer

Enable BFD on the Direct Connect virtual interface.

Answer

Recreate the virtual interface with a new VLAN ID.