The answer is the application's session cookie having a shorter expiration than the ALB's stickiness duration. This mismatch causes session loss because the ALB relies on its own 'AWSALB' cookie to maintain stickiness for one hour, but if the application's cookie expires sooner, the user's session state is invalidated on the backend, forcing a logout even though the ALB would still route subsequent requests to the same target. On the AWS Certified SysOps Administrator Associate SOA-C02 exam, this question tests your understanding of how application-managed cookies interact with ALB-generated stickiness cookies, a common trap where candidates assume the ALB's duration alone controls session persistence. Remember the key insight: the ALB routes traffic, but the application owns the session—if the app's cookie dies first, the session dies with it. A useful memory tip is "App cookie expiry is the weak link; ALB stickiness is just the routing link."
SOA-C02 Networking and Content Delivery Practice Question
This SOA-C02 practice question tests your understanding of networking and content delivery. 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 company has a web application running on EC2 instances behind an Application Load Balancer (ALB). The application uses sticky sessions (session affinity) based on cookies. Recently, the SysOps team noticed that user sessions are being lost intermittently, causing users to be logged out. The team checks the ALB configuration and finds that the stickiness is enabled with a cookie name 'AWSALB' and duration of 1 hour. The application also sets its own cookie. What is the most likely cause of session loss?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The application's session cookie has a shorter expiration than the ALB's stickiness duration
Option A is correct because if the application's cookie is set to expire before the ALB's stickiness duration, the session may be lost when the application cookie expires. Option B is wrong because cross-zone load balancing does not affect stickiness. Option C is wrong because health checks do not remove stickiness unless the instance becomes unhealthy. Option D is wrong because the ALB generates its own cookie; the application setting a cookie does not interfere unless it overwrites.
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.
✗
The ALB's health check interval is too short, causing instances to be marked unhealthy
Why it's wrong here
If instances are healthy, stickiness is maintained.
✗
The application cookie is overwriting the ALB's stickiness cookie
Why it's wrong here
The ALB uses its own cookie name; they do not interfere.
✗
Cross-zone load balancing is disabled on the ALB
Why it's wrong here
Cross-zone load balancing does not affect session stickiness.
✓
The application's session cookie has a shorter expiration than the ALB's stickiness duration
Why this is correct
If the application cookie expires, the session is lost even though the ALB still routes to the same instance.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
What to study next
Got this wrong? Here's your next step.
Identify which SOA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Networking and Content Delivery — This question tests Networking and Content Delivery — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The application's session cookie has a shorter expiration than the ALB's stickiness duration — Option A is correct because if the application's cookie is set to expire before the ALB's stickiness duration, the session may be lost when the application cookie expires. Option B is wrong because cross-zone load balancing does not affect stickiness. Option C is wrong because health checks do not remove stickiness unless the instance becomes unhealthy. Option D is wrong because the ALB generates its own cookie; the application setting a cookie does not interfere unless it overwrites.
What should I do if I get this SOA-C02 question wrong?
Identify which SOA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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 →
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.
This SOA-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 SOA-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.