JNCIS-ENT High Availability Practice Question
You are performing a pre-check for an ISSU on an MX series router. You execute 'request system software in-service check' and the system reports an error indicating that graceful restart or NSR is not properly configured for active routing protocols. How do you resolve this?
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 Nonstop Active Routing (NSR) or Graceful Restart for all active interior and exterior routing protocols before re-running the check.
ISSU requires that either NSR or Graceful Restart is enabled for all running routing protocols to prevent loss of state during the control plane upgrade.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Manually restart the routing protocol daemon (rpd) on both Routing Engines simultaneously.
Why it's wrong here
Restarting rpd simultaneously causes a total control plane outage and does not satisfy ISSU pre-checks.
- ✓
Configure Nonstop Active Routing (NSR) or Graceful Restart for all active interior and exterior routing protocols before re-running the check.
Why this is correct
ISSU requires routing protocols to be capable of surviving control plane restarts via NSR or Graceful Restart helper/restart mechanisms.
- ✗
Disable GRES to bypass protocol state verification checks.
Why it's wrong here
Disabling GRES will cause ISSU to fail entirely since GRES is a strict prerequisite.
- ✗
Set the virtual-chassis mastership-priority to 255 on both routing engines.
Why it's wrong here
Virtual-chassis priorities apply to EX series switches, not modular MX series routing platforms.
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.