- A
Replace the local file system storage with an Amazon ElastiCache for Redis cluster that is external to the instances.
Why wrong: Requires application code changes to use Redis.
- B
Enable sticky sessions (session affinity) on the ALB and configure the Auto Scaling group to use a lifecycle hook to drain connections before instance termination.
Sticky sessions route user to same instance; lifecycle hook ensures sessions complete before termination.
- C
Store session data in Amazon DynamoDB and configure the application to use the DynamoDB session handler.
Why wrong: Requires code changes.
- D
Configure the Auto Scaling group to scale down based on memory utilization rather than CPU, to reduce termination frequency.
Why wrong: Does not solve session persistence; still loses sessions when instance terminates.
Quick Answer
The correct solution is to enable ALB sticky sessions for session persistence and configure Auto Scaling lifecycle hooks to drain connections before instance termination. Sticky sessions, also known as session affinity, ensure that all requests from a user during a session are routed to the same EC2 instance, which preserves the session data stored in the local file system of that instance. The lifecycle hook is critical because it pauses instance termination, allowing the ALB to finish serving active connections before the instance is fully terminated, preventing abrupt session timeouts. On the AWS Certified Solutions Architect Professional SAP-C02 exam, this scenario tests your ability to work around legacy code constraints by leveraging native AWS features rather than requiring application modifications—a common trap is jumping to ElastiCache or DynamoDB, which demand code changes. Remember the key pairing: sticky sessions keep users pinned to their instance, while lifecycle hooks ensure a graceful exit. A useful memory tip is "Stick and Drain"—the ALB sticks the user, the hook drains the instance.
SAP-C02 Continuous Improvement for Existing Solutions Practice Question
This SAP-C02 practice question tests your understanding of continuous improvement for existing solutions. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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.
An e-commerce company runs a customer-facing application on AWS. The application architecture includes an Application Load Balancer (ALB), EC2 instances in an Auto Scaling group, and an Amazon RDS for MySQL Multi-AZ DB instance. The application uses a custom web server that stores session data in a local file system. During peak traffic, users experience session timeouts and errors. The operations team observes that the Auto Scaling group launches new instances and terminates old ones frequently. The team wants to improve the user experience and ensure session persistence. The Solutions Architect proposes to modify the application to store session data in an external store. However, due to a legacy code dependency, the application cannot be modified in the short term. Which solution should the Solutions Architect implement to resolve the session persistence issue without modifying the application?
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
Enable sticky sessions (session affinity) on the ALB and configure the Auto Scaling group to use a lifecycle hook to drain connections before instance termination.
Option A is correct because enabling sticky sessions on the ALB ensures that a user's requests are always routed to the same instance, preserving the local session files. Option B is wrong because ElastiCache still requires application code changes to use it. Option C is wrong because DynamoDB also requires code changes. Option D is wrong because scaling down based on memory does not prevent session loss; it may cause more terminations.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Replace the local file system storage with an Amazon ElastiCache for Redis cluster that is external to the instances.
Why it's wrong here
Requires application code changes to use Redis.
- ✓
Enable sticky sessions (session affinity) on the ALB and configure the Auto Scaling group to use a lifecycle hook to drain connections before instance termination.
Why this is correct
Sticky sessions route user to same instance; lifecycle hook ensures sessions complete before termination.
Related concept
Static NAT maps one inside address to one outside address.
- ✗
Store session data in Amazon DynamoDB and configure the application to use the DynamoDB session handler.
Why it's wrong here
Requires code changes.
- ✗
Configure the Auto Scaling group to scale down based on memory utilization rather than CPU, to reduce termination frequency.
Why it's wrong here
Does not solve session persistence; still loses sessions when instance terminates.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
- Static NAT maps one inside address to one outside address.
- PAT allows many inside hosts to share one public address using ports.
- Inside local and inside global describe the private and translated addresses.
- NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
- Identify inside and outside interfaces first.
- Check whether the scenario needs static NAT, dynamic NAT or PAT.
- Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
What to study next
Got this wrong? Here's your next step.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related SAP-C02 NAT questions on configuration and troubleshooting.
- →
Continuous Improvement for Existing Solutions — study guide chapter
Learn the concepts, then practise the questions
- →
Continuous Improvement for Existing Solutions practice questions
Targeted practice on this topic area only
- →
All SAP-C02 questions
1,746 questions across all exam domains
- →
AWS Certified Solutions Architect Professional SAP-C02 study guide
Full concept coverage aligned to exam objectives
- →
SAP-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related SAP-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Design Solutions for Organizational Complexity practice questions
Practise SAP-C02 questions linked to Design Solutions for Organizational Complexity.
Design for New Solutions practice questions
Practise SAP-C02 questions linked to Design for New Solutions.
Continuous Improvement for Existing Solutions practice questions
Practise SAP-C02 questions linked to Continuous Improvement for Existing Solutions.
Accelerate Workload Migration and Modernization practice questions
Practise SAP-C02 questions linked to Accelerate Workload Migration and Modernization.
SAA-C03 VPC practice questions
Practise SAP-C02 questions linked to SAA-C03 VPC.
SAA-C03 S3 lifecycle policy questions
Practise SAP-C02 questions linked to SAA-C03 S3 lifecycle policy questions.
SAA-C03 RDS Multi-AZ questions
Practise SAP-C02 questions linked to SAA-C03 RDS Multi-AZ questions.
SAA-C03 IAM policy practice questions
Practise SAP-C02 questions linked to SAA-C03 IAM policy.
SAA-C03 Route 53 failover questions
Practise SAP-C02 questions linked to SAA-C03 Route 53 failover questions.
SAA-C03 CloudFront practice questions
Practise SAP-C02 questions linked to SAA-C03 CloudFront.
SAA-C03 NAT gateway questions
Practise SAP-C02 questions linked to SAA-C03 NAT gateway questions.
SAA-C03 VPC endpoint questions
Practise SAP-C02 questions linked to SAA-C03 VPC endpoint questions.
Practice this exam
Start a free SAP-C02 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 SAP-C02 question test?
Continuous Improvement for Existing Solutions — This question tests Continuous Improvement for Existing Solutions — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: Enable sticky sessions (session affinity) on the ALB and configure the Auto Scaling group to use a lifecycle hook to drain connections before instance termination. — Option A is correct because enabling sticky sessions on the ALB ensures that a user's requests are always routed to the same instance, preserving the local session files. Option B is wrong because ElastiCache still requires application code changes to use it. Option C is wrong because DynamoDB also requires code changes. Option D is wrong because scaling down based on memory does not prevent session loss; it may cause more terminations.
What should I do if I get this SAP-C02 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related SAP-C02 NAT questions on configuration and troubleshooting.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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 →
Last reviewed: Jun 20, 2026
This SAP-C02 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 SAP-C02 exam.
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.
Sign in to join the discussion.