- A
Add a static host entry in the web servers' hosts file pointing to the DR database IP
Why wrong: Static entries require manual updates during failover, which is not scalable and prone to errors.
- B
Increase the DNS TTL to 86400 seconds to ensure all caches are updated quickly
Why wrong: Increasing TTL would cause caches to hold stale records longer, making the problem worse.
- C
Configure the web servers to use a different DNS resolver that does not cache
Why wrong: Changing DNS resolvers does not eliminate caching; most resolvers still cache.
- D
Implement a load balancer or proxy with a virtual IP that can be switched during failover, and update the web server configuration to connect to the virtual IP
A virtual IP (VIP) can be moved between data centers via BGP or similar, so web servers always connect to the same IP, avoiding DNS caching issues.
Quick Answer
The correct answer is to implement a load balancer or proxy with a virtual IP (VIP) that can be switched during failover, and update the web server configuration to connect to that VIP. This solution directly resolves the database failover issue caused by stale DNS cache because the VIP acts as a stable, logical endpoint that moves with the active database, eliminating any dependency on DNS resolution or TTL expiration. On the ISC2 Certified in Cybersecurity CC exam, this scenario tests your understanding of how to decouple application components from physical IP addresses to ensure high availability, often appearing as a trap where candidates mistakenly focus on lowering DNS TTL or forcing cache flushes instead of architecting a persistent connection point. Remember the key principle: a VIP is like a fixed street address for a moving house—the web servers never need to ask for directions again. Memory tip: “VIP beats DNS delay” to recall that a virtual IP bypasses cache problems entirely.
ISC2 CC Business Continuity, DR & Incident Response Practice Question
This CC practice question tests your understanding of business continuity, dr & incident response. 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 mid-sized e-commerce company has a primary data center in New York and a disaster recovery site in Dallas. The application stack includes a web server, application server, and a PostgreSQL database. The database uses synchronous replication to the DR site. During a routine failover test, the IT team discovers that after failing over to Dallas, the web servers in New York continue to attempt connections to the original database IP, causing application errors. The DNS records have been updated to point to the DR database IP, but the web servers are not refreshing their DNS cache. The company uses a standard TTL of 300 seconds. The IT manager needs a solution that ensures minimal disruption during future failovers. Which action should be taken?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"primary"Why it matters: Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
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
Implement a load balancer or proxy with a virtual IP that can be switched during failover, and update the web server configuration to connect to the virtual IP
Option D is correct because it decouples the web servers from the database IP address by introducing a load balancer or proxy with a virtual IP (VIP). During failover, the VIP is simply moved to the DR database, and the web servers continue connecting to the same VIP without any DNS dependency or cache refresh issues. This eliminates the problem of stale DNS caches and ensures minimal disruption, as the connection endpoint remains constant.
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.
- ✗
Add a static host entry in the web servers' hosts file pointing to the DR database IP
Why it's wrong here
Static entries require manual updates during failover, which is not scalable and prone to errors.
- ✗
Increase the DNS TTL to 86400 seconds to ensure all caches are updated quickly
Why it's wrong here
Increasing TTL would cause caches to hold stale records longer, making the problem worse.
- ✗
Configure the web servers to use a different DNS resolver that does not cache
Why it's wrong here
Changing DNS resolvers does not eliminate caching; most resolvers still cache.
- ✓
Implement a load balancer or proxy with a virtual IP that can be switched during failover, and update the web server configuration to connect to the virtual IP
Why this is correct
A virtual IP (VIP) can be moved between data centers via BGP or similar, so web servers always connect to the same IP, avoiding DNS caching issues.
Clue confirmation
The clue word "primary" 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
ISC2 often tests the misconception that DNS TTL adjustments or cache clearing are sufficient for failover scenarios, but the trap here is that DNS-based solutions inherently introduce propagation delays and cache inconsistencies, whereas a virtual IP provides immediate, transparent failover without relying on DNS resolution.
Detailed technical explanation
How to think about this question
A virtual IP (VIP) is typically managed by a load balancer or a clustering solution (e.g., HAProxy, F5, or keepalived with VRRP) that can be moved between data centers using BGP or DNS-based GSLB. Under the hood, the VIP is a floating IP address that is advertised from the active site; during failover, the VIP is reassigned to the DR site via IP takeover, and the web servers' TCP connections remain directed to the same IP, avoiding any DNS resolution delays. In real-world scenarios, this approach is standard for stateful databases like PostgreSQL with synchronous replication, where connection persistence is critical.
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 security analyst at a medium-sized enterprise encounters this scenario during an investigation or architecture review. The correct answer reflects best practice for the specific threat or control described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Security exam questions test whether you can match controls to threats in context — not just recall definitions.
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.
- →
Business Continuity, DR & Incident Response — study guide chapter
Learn the concepts, then practise the questions
- →
Business Continuity, DR & Incident Response practice questions
Targeted practice on this topic area only
- →
All CC questions
500 questions across all exam domains
- →
ISC2 Certified in Cybersecurity CC study guide
Full concept coverage aligned to exam objectives
- →
CC practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related CC practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Access Controls Concepts practice questions
Practise CC questions linked to Access Controls Concepts.
Business Continuity, DR & Incident Response practice questions
Practise CC questions linked to Business Continuity, DR & Incident Response.
Security Principles practice questions
Practise CC questions linked to Security Principles.
Network Security practice questions
Practise CC questions linked to Network Security.
Security Operations practice questions
Practise CC questions linked to Security Operations.
CC fundamentals practice questions
Practise CC questions linked to CC fundamentals.
CC scenario practice questions
Practise CC questions linked to CC scenario.
CC troubleshooting practice questions
Practise CC questions linked to CC troubleshooting.
Practice this exam
Start a free CC 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 CC question test?
Business Continuity, DR & Incident Response — This question tests Business Continuity, DR & Incident Response — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Implement a load balancer or proxy with a virtual IP that can be switched during failover, and update the web server configuration to connect to the virtual IP — Option D is correct because it decouples the web servers from the database IP address by introducing a load balancer or proxy with a virtual IP (VIP). During failover, the VIP is simply moved to the DR database, and the web servers continue connecting to the same VIP without any DNS dependency or cache refresh issues. This eliminates the problem of stale DNS caches and ensures minimal disruption, as the connection endpoint remains constant.
What should I do if I get this CC 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: "primary". Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
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 →
Last reviewed: Jun 30, 2026
This CC practice question is part of Courseiva's free ISC2 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 CC 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.