C100DBA Server Administration Practice Question
Exhibit
rs.conf() output:
{ "_id": "mySet", "members": [
{ "_id": 0, "host": "n1:27017", "priority": 1 },
{ "_id": 1, "host": "n2:27017", "priority": 0 },
{ "_id": 2, "host": "n3:27017", "priority": 1 }
]}Refer to the exhibit. What is the implication of setting the priority of n2 to 0?
⚠ Common exam trap
Candidates often mistake a priority of 0 to mean the node cannot be read from or that it is completely offline, forgetting it only prevents it from becoming primary.
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
✓
n2 will never become the primary node.
A priority of 0 designates a member as a 'passive' node. It can never become the primary, even if all other nodes are down. This configuration is often used for nodes in different data centers to prevent them from taking over as primary, which could cause latency issues for applications. Understanding this is vital for controlling election behavior and ensuring that the primary node is always located in a preferred, low-latency environment for the application workload.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
n2 will be excluded from the voting process entirely.
Why it's wrong here
A priority of 0 does not remove a node from the voting process. The node still participates in elections by casting a vote for other candidates; it simply cannot be elected as a primary itself. The node remains a fully participating member of the replica set's consensus mechanism.
- ✓
n2 will never become the primary node.
Why this is correct
Priority 0 members are ineligible to become primary. This configuration is explicitly used to prevent a specific node from becoming the primary, ensuring that only nodes with higher priority values can take on the primary role during an election, which is useful for regional failover or specialized hardware setups.
- ✗
n2 will stop replicating data from the primary.
Why it's wrong here
Priority does not control data synchronization. A priority 0 node continues to replicate data from the current primary just like any other secondary. It remains an up-to-date copy of the data, which is useful for read-scaling or disaster recovery purposes, even though it cannot participate as a primary.
- ✗
n2 will be removed from the replica set automatically.
Why it's wrong here
Setting priority to 0 is a configuration change, not a removal command. The node remains part of the replica set configuration and will continue to participate in heartbeat signals and elections as a voting member. It is still a fully functional member of the set, just ineligible for primary.
About these practice questions
Courseiva writes every C100DBA question from scratch — 222 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 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.