JNCIS-ENT Spanning Tree Practice Question
When configuring MSTP, how is the regional maximum hop count enforced across switches within the same MST region?
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
✓
BPDUs carry a hop count that is decremented by each bridge; when it reaches zero, the BPDU is dropped.
Each switch decrements the hop count field in the MSTP BPDU before forwarding it; if the hop count reaches zero, the BPDU is discarded, preventing loops in large MSTP deployments.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The regional root periodically floods drop-commands if the network diameter exceeds the limit.
Why it's wrong here
Hop counting is distributed, not centrally commanded.
- ✓
BPDUs carry a hop count that is decremented by each bridge; when it reaches zero, the BPDU is dropped.
Why this is correct
MSTP uses a hop count mechanism similar to IP TTL to limit BPDU propagation within a region.
- ✗
Switches drop any incoming BPDUs that exceed the statically configured Max Age timer.
Why it's wrong here
Max Age is timer-based, whereas hop count is decremented per switch hop.
- ✗
Ports exceeding the hop count are automatically placed into the error-disabled state.
Why it's wrong here
Exceeding the hop count results in dropping the BPDU, not error-disabling the port.
Visual reference
About these practice questions
This JNCIS-ENT question is part of Courseiva's 506-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 August 2026 · checked against the official Juniper Networks exam blueprint
This JNCIS-ENT practice question is part of Courseiva's free Juniper Networks 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 JNCIS-ENT exam.