JNCIS-ENT Layer 2 Switching And VLANs Practice Question
An engineer is configuring a trunk port on an EX Series switch and needs to manage untagged traffic, allowed VLANs, and native VLAN tagging behavior. Which THREE configurations are valid in Junos for a trunk interface? (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
✓
set interfaces ge-0/0/9 unit 0 family ethernet-switching vlan members [ 10 20 30 ]
Trunk interface configurations in Junos allow setting trunk mode, native VLAN ID, and explicit or member-all VLAN membership lists.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
set interfaces ge-0/0/9 unit 0 family ethernet-switching vlan members [ 10 20 30 ]
Why this is correct
Correct. Specifies an explicit allowed member list.
- ✓
set interfaces ge-0/0/9 unit 0 family ethernet-switching native-vlan-id 10
Why this is correct
Correct. Specifies the native VLAN for untagged frames.
- ✓
set interfaces ge-0/0/9 unit 0 family ethernet-switching interface-mode trunk
Why this is correct
Correct. Sets the port mode to trunk.
- ✗
set interfaces ge-0/0/9 unit 0 family ethernet-switching trunk-encapsulation dot1q-only
Why it's wrong here
Trunk encapsulation on enterprise EX switches uses standard IEEE 802.1Q without this specific command.
- ✗
set interfaces ge-0/0/9 unit 0 family ethernet-switching access-vlan 10
Why it's wrong here
Access-vlan is not a valid keyword for trunk interfaces.
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.