C100DBA Sharding Practice Question
An administrator notices that the MongoDB balancer is actively migrating chunks during peak business hours, causing noticeable application latency spikes. What is the standard administrative approach to mitigate this performance impact?
⚠ Common exam trap
Candidates often think they need to completely disable the balancer during business hours, missing that configuring a maintenance window is the correct granular solution.
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
✓
Configure a balancer window by updating the settings collection in the config database to restrict migrations to specific off-peak hours.
Configuring a balancer window restricts chunk migrations to off-peak hours, preventing background balancing traffic from contending with production application workloads. Mastering balancer scheduling controls allows DBAs to maintain cluster health and optimal data distribution without disrupting user experience during critical business hours.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Configure a balancer window by updating the settings collection in the config database to restrict migrations to specific off-peak hours.
Why this is correct
Configure a balancer window by updating the settings collection in the config database to restrict migrations to specific off-peak hours. Setting a defined active time window ensures that resource-intensive chunk migrations occur exclusively during scheduled maintenance periods or low-traffic intervals.
- ✗
Permanently terminate the mongos process responsible for orchestrating chunk migrations across the cluster nodes.
Why it's wrong here
Permanently terminate the mongos process responsible for orchestrating chunk migrations across the cluster nodes. Terminating query routers disrupts client connectivity and does not safely stop balancing activities, which are managed centrally by the config server primary.
- ✗
Execute the dropDatabase command on every shard to purge unbalanced chunks instantly and reset the cluster.
Why it's wrong here
Execute the dropDatabase command on every shard to purge unbalanced chunks instantly and reset the cluster. Dropping databases destroys all production user data and is entirely unrelated to managing or scheduling background chunk migration activities.
- ✗
Disable journaling across all shard replica set members to accelerate background data migration speeds.
Why it's wrong here
Disable journaling across all shard replica set members to accelerate background data migration speeds. Disabling journaling creates severe risks of unrecoverable data loss during sudden power failures and does not properly address balancer scheduling conflicts.
About these practice questions
One of 222 original C100DBA practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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.