The correct answer is to modify the wait_timeout parameter in the DB parameter group to a lower value. This parameter defines the number of seconds the server waits for activity on a non-interactive connection before closing it; by reducing it from the default 28800 seconds (8 hours), Amazon RDS for MySQL will automatically terminate idle connections in the 'sleep' state, freeing up resources and improving performance. On the AWS Certified Database Specialty DBS-C01 exam, this question tests your understanding of MySQL-specific parameter tuning versus other connection management tools—a common trap is confusing RDS Proxy (which pools connections but does not terminate idle ones) with wait_timeout, or thinking that killing connections manually is automated. Remember the memory tip: "Wait for timeout, not for manual kill"—if the connection is sleeping, let the parameter do the work.
DBS-C01 Management and Operations Practice Question
This DBS-C01 practice question tests your understanding of management and operations. 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.
A company is running an Amazon RDS for MySQL DB instance. The database performance has degraded over time. The DBA suspects that the issue is due to a high number of connections that are in a 'sleep' state from a legacy application. What is the MOST effective solution to automatically terminate idle connections?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Modify the 'wait_timeout' parameter in the DB parameter group to a lower value.
Option C is correct because Amazon RDS for MySQL supports the 'wait_timeout' parameter, which automatically closes idle connections after the specified number of seconds. Reducing this value from the default 28800 seconds will terminate sleeping connections sooner. Option A is incorrect because manually killing connections is not automated. Option B is incorrect because RDS Proxy does not terminate idle connections; it manages connection pooling. Option D is incorrect because modifying 'max_connections' does not affect idle connections.
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.
✓
Modify the 'wait_timeout' parameter in the DB parameter group to a lower value.
Why this is correct
This parameter controls how long the server waits for activity on a non-interactive connection before closing it.
Related concept
Static NAT maps one inside address to one outside address.
✗
Increase the 'max_connections' parameter to accommodate more idle connections.
Why it's wrong here
Increasing max_connections only allows more connections, it does not terminate idle ones.
✗
Enable Amazon RDS Proxy to manage connection pooling and automatically close idle connections.
Why it's wrong here
RDS Proxy pools connections but does not terminate idle ones based on sleep time.
✗
Use a script to run 'SHOW PROCESSLIST' and manually kill idle connections.
Why it's wrong here
Manual intervention is not automated and not scalable.
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 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. NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated. 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.
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 DBS-C01 NAT questions on configuration and troubleshooting.
Management and Operations — This question tests Management and Operations — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: Modify the 'wait_timeout' parameter in the DB parameter group to a lower value. — Option C is correct because Amazon RDS for MySQL supports the 'wait_timeout' parameter, which automatically closes idle connections after the specified number of seconds. Reducing this value from the default 28800 seconds will terminate sleeping connections sooner. Option A is incorrect because manually killing connections is not automated. Option B is incorrect because RDS Proxy does not terminate idle connections; it manages connection pooling. Option D is incorrect because modifying 'max_connections' does not affect idle connections.
What should I do if I get this DBS-C01 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 DBS-C01 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 →
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 DBS-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 DBS-C01 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.