Question 86 of 1,705
Network Security, Compliance and GovernancemediumMultiple SelectObjective-mapped

Quick Answer

The correct answer is to configure the RDS security group to allow inbound traffic on port 3306 from the EC2 instance security group, alongside referencing the ALB security group as the source in the EC2 security group rule. This follows security group referencing best practices by using logical security group IDs rather than static IP ranges, which creates a dynamic, tightly scoped trust boundary that automatically adapts as the ALB’s elastic network interfaces scale. On the AWS Certified Advanced Networking Specialty ANS-C01 exam, this concept tests your understanding of stateful, resource-level access control versus traditional CIDR-based rules—a common trap is to mistakenly use the ALB’s private IP range, which breaks auto-scaling and introduces management overhead. Remember the memory tip: “Reference the source, not the IP—let the group do the filtering for you.”

ANS-C01 Network Security, Compliance and Governance Practice Question

This ANS-C01 practice question tests your understanding of network security, compliance and governance. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.

A security engineer is designing a security group configuration for a web application that consists of an Application Load Balancer (ALB), Amazon EC2 instances in an Auto Scaling group, and an Amazon RDS database. Which TWO actions should the engineer take to follow security best practices? (Choose TWO.)

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

  • Clue: "best"

    Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.

Question 1mediummulti select
Full question →

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

Configure the EC2 instance security group to allow inbound traffic on port 443 from the ALB security group.

Option B is correct because referencing the ALB security group as the source in the EC2 security group rule ensures that only traffic originating from the ALB (and not any other source) is allowed on port 443. This follows the security best practice of using security group references instead of IP ranges, providing a tighter, more dynamic access control that automatically scales with the ALB's elastic network interfaces.

Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • Configure the RDS security group to allow inbound traffic on port 3306 from 0.0.0.0/0.

    Why it's wrong here

    Should not allow all traffic.

  • Configure the EC2 instance security group to allow inbound traffic on port 443 from the ALB security group.

    Why this is correct

    Best practice: reference security group instead of CIDR.

    Clue confirmation

    The clue word "best" in the question point toward this answer.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Configure the RDS security group to allow inbound traffic on port 3306 from the EC2 instance security group.

    Why this is correct

    Best practice: restrict database access to app servers.

    Clue confirmation

    The clue word "best" in the question point toward this answer.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Configure the ALB security group to allow inbound traffic on port 443 from the security group of the EC2 instances.

    Why it's wrong here

    ALB should allow inbound from internet, not EC2.

  • Configure the ALB security group to allow inbound traffic on port 80 from the security group of the EC2 instances.

    Why it's wrong here

    ALB inbound should be from clients.

Common exam traps

Common exam trap: answer the scenario, not the keyword

AWS often tests the misconception that security groups should be configured with IP ranges (e.g., 0.0.0.0/0) for simplicity, rather than using security group references to enforce least-privilege access between tiers.

Detailed technical explanation

How to think about this question

Security group references (e.g., sg-xxxxxxx) are resolved at the AWS network layer to the private IP addresses of the referenced resources, enabling dynamic updates without manual IP management. For RDS, using the EC2 security group as the source on port 3306 ensures that only EC2 instances in that group can connect, even if they are replaced or scaled. In a real-world scenario, if the Auto Scaling group launches new instances, they automatically inherit the security group and gain database access without additional configuration.

KKey Concepts to Remember

  • Read the scenario before looking for a memorised answer.
  • Find the constraint that changes the correct option.
  • Eliminate answers that are true in general but not in this case.

TExam Day Tips

  • Watch for words such as best, first, most likely and least administrative effort.
  • Review why wrong options are wrong, not only why the correct option is correct.

Key takeaway

Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.

Real-world example

How this comes up in practice

A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.

What to study next

Got this wrong? Here's your next step.

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

Related practice questions

Related ANS-C01 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Practice this exam

Start a free ANS-C01 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

FAQ

Questions learners often ask

What does this ANS-C01 question test?

Network Security, Compliance and Governance — This question tests Network Security, Compliance and Governance — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Configure the EC2 instance security group to allow inbound traffic on port 443 from the ALB security group. — Option B is correct because referencing the ALB security group as the source in the EC2 security group rule ensures that only traffic originating from the ALB (and not any other source) is allowed on port 443. This follows the security best practice of using security group references instead of IP ranges, providing a tighter, more dynamic access control that automatically scales with the ALB's elastic network interfaces.

What should I do if I get this ANS-C01 question wrong?

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

Are there clue words in this question I should notice?

Yes — watch for: "best". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.

What is the key concept behind this question?

Read the scenario before looking for a memorised answer.

About these practice questions

Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

Same concept, more angles

2 more ways this is tested on ANS-C01

These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.

Variation 1. A network engineer is designing a security group for a web application that must allow inbound HTTPS traffic from the internet and outbound traffic to an RDS MySQL database. The web servers are in a public subnet and the RDS database is in a private subnet. What is the most secure way to configure the security groups?

medium
  • A.Web SG: inbound HTTPS from 0.0.0.0/0; outbound MySQL to DB SG. DB SG: inbound MySQL from Web SG.
  • B.Web SG: inbound HTTPS from 0.0.0.0/0; outbound 0.0.0.0/0. DB SG: inbound MySQL from Web SG.
  • C.Web SG: inbound HTTPS from 0.0.0.0/0; outbound MySQL to DB SG. DB SG: inbound MySQL from 0.0.0.0/0.
  • D.Web SG: inbound HTTPS from 0.0.0.0/0; outbound 0.0.0.0/0. DB SG: inbound MySQL from 0.0.0.0/0.

Why A: Option B is correct because the web server security group allows inbound HTTPS (443) from anywhere and outbound MySQL (3306) to the database security group. The database security group allows inbound MySQL from the web server security group. Option A is wrong because allowing outbound traffic to 0.0.0.0/0 is too permissive. Option C is wrong because the database security group should reference the web server security group, not vice versa. Option D is wrong because the database should only allow inbound from the web server security group, not from the internet.

Variation 2. A company is designing a network security architecture for a VPC that hosts a multi-tier application. The security team requires that the web tier can only be accessed from the internet, the application tier can only be accessed from the web tier, and the database tier can only be accessed from the application tier. Additionally, the team needs to ensure that no traffic can bypass these controls. Which THREE actions should the team take?

hard
  • A.Use security group rules that reference other security groups as sources.
  • B.Configure security groups to allow only necessary traffic between tiers.
  • C.Configure network ACLs (NACLs) to allow only necessary traffic between subnets as a defense-in-depth measure.
  • D.Enable VPC Flow Logs on all subnets and send logs to Amazon S3.
  • E.Attach an internet gateway to the VPC and add a default route to the internet gateway in the web tier subnet's route table.

Why A: Security group rules can reference other security groups as sources, which allows the web tier security group to permit traffic only from the application tier security group, and the application tier security group to permit traffic only from the database tier security group. This creates a logical, stateful firewall that enforces the required traffic flow between tiers without relying on IP addresses, ensuring that no traffic can bypass the controls even if subnet configurations change.

Keep practising

More ANS-C01 practice questions

Last reviewed: Jun 30, 2026

Question Discussion

Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.

Loading comments…

Sign in to join the discussion.

This ANS-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the ANS-C01 exam.