C100DBA Replication Practice Question
Which member type in a MongoDB replica set is best suited for a geographically distant data center to provide read-only access without influencing elections?
⚠ Common exam trap
Candidates often suggest deploying an arbiter for remote read-only data centers, forgetting that arbiters do not store any data.
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
✓
Priority 0 Secondary
A priority 0 secondary is ideal for this scenario. By setting the priority to zero, the node is ineligible to become primary, preventing it from participating in elections. This is critical for nodes in remote locations where high latency could disrupt election timing or cause unnecessary re-elections, while still providing low-latency read access to users in that specific geographical region.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Arbiter
Why it's wrong here
Arbiters do not store data; they only participate in elections. Using an arbiter in a remote data center would provide no benefit for read operations, as they are not designed to serve client queries. They exist solely to help the replica set achieve a majority vote for electing new primaries.
- ✗
Hidden Member
Why it's wrong here
While a hidden member does not receive traffic from the mongos or client drivers, it is not optimized for read performance. Furthermore, hidden members can still become primary if their priority is greater than zero, which could cause significant latency issues if a node in a remote region becomes the primary.
- ✓
Priority 0 Secondary
Why this is correct
A priority 0 secondary cannot be elected primary, making it perfect for remote sites. It maintains a full copy of the data, which allows it to serve read requests locally. Because it cannot become primary, it eliminates the risk of a high-latency node taking control of the entire cluster's operations.
- ✗
Delayed Secondary
Why it's wrong here
A delayed secondary is primarily used for disaster recovery, keeping data that is intentionally behind the primary to protect against human error or accidental deletions. Its data is not current, making it unsuitable for applications that require low-latency access to the latest data in a remote geographic region.
About these practice questions
This C100DBA question is part of Courseiva's 222-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official MongoDB exam blueprint
This C100DBA practice question is part of Courseiva's free MongoDB 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 C100DBA exam.