JNCIP-ENT IP Multicast Practice Question
An engineer is troubleshooting a multicast forwarding issue where data from a specific source is not reaching receivers in a remote PIM sparse-mode domain. Which THREE operational commands and diagnostic steps should be used to verify the multicast forwarding state and RPF path on a Junos router? (Choose three)
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
✓
Run 'show pim join' to inspect upstream neighbor information and verify the RPF interface for the source.
To troubleshoot multicast traffic forwarding and RPF failures in Junos, operators check the multicast forwarding cache using 'show multicast route', verify the upstream RPF neighbor using 'show pim join', and inspect IGMP membership states.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Run 'show ospf database multicast' to verify LSA type 6 propagation.
Why it's wrong here
MOSPF uses type 6 LSAs, but standard enterprise deployments use PIM, and MOSPF does not use this command syntax.
- ✓
Run 'show pim join' to inspect upstream neighbor information and verify the RPF interface for the source.
Why this is correct
The 'show pim join' command displays PIM join state and confirms the upstream RPF neighbor toward the source or RP.
- ✓
Run 'show igmp group' to verify that receivers have successfully joined the multicast group on the local interface.
Why this is correct
Checking local IGMP membership via 'show igmp group' ensures that receivers are actively requesting the stream on the last-hop router.
- ✗
Run 'show bgp summary multicast-unicast' to verify BGP routing tables for multicast RPF checks.
Why it's wrong here
Multicast RPF checks rely on the unicast routing table (or MBGP if explicitly configured), but 'bgp summary multicast-unicast' is not the correct troubleshooting syntax for standard PIM RPF verification.
- ✓
Run 'show multicast route' to verify if (S,G) or (*,G) entries exist and check packet forwarding counters.
Why this is correct
The 'show multicast route' command displays the mroute table, showing incoming/outgoing interfaces and packet/byte counters.
About these practice questions
This JNCIP-ENT question is part of Courseiva's 332-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 JNCIP-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 JNCIP-ENT exam.