hardMultiple ChoiceObjective-mapped
CAS-004 Practice Question: A large enterprise is designing a disaster…
A large enterprise is designing a disaster recovery site that must support rapid failover with minimal data loss. The primary data center is 50 miles away. The RPO is 1 minute, and RTO is 15 minutes. Which replication strategy best meets these requirements?
⚠ Common exam trap
A common mix-up: candidates choose asynchronous replication (Option D) thinking 'continuous data protection' implies zero data loss, but they overlook that asynchronous replication inherently introduces a write acknowledgment delay, which can still result in data loss during a failure, and the recovery process may not meet the aggressive RTO.
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
✓
Synchronous replication over dedicated low-latency fiber links.
Synchronous replication writes data to both the primary and secondary sites simultaneously before acknowledging the write to the application, ensuring zero data loss at the storage layer. With dedicated low-latency fiber links over 50 miles, the round-trip time can be kept under 1 ms, meeting the 1-minute RPO and enabling rapid failover within the 15-minute RTO. This strategy guarantees transactional consistency and immediate availability at the DR site.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Log shipping with a 5-minute delay.
Why it's wrong here
Log shipping with delay exceeds the RPO.
- ✓
Synchronous replication over dedicated low-latency fiber links.
Why this is correct
Synchronous replication ensures zero data loss and can meet the required RPO and RTO if latency is low enough.
- ✗
Scheduled snapshot-based replication every 30 minutes.
Why it's wrong here
Snapshots every 30 minutes do not meet the 1-minute RPO.
- ✗
Asynchronous replication with continuous data protection.
Why it's wrong here
Asynchronous replication may have seconds to minutes of lag, potentially exceeding the 1-minute RPO.
Visual reference
Go deeper
Related to this question
About these practice questions
Courseiva writes every CAS-005 question from scratch — 968 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CAS-005 practice question is part of Courseiva's free CompTIA 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 CAS-005 exam.