This 350-401 practice question tests your understanding of vlans and trunking. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Which of the following is a valid VLAN range that can be created on a Cisco IOS switch?
VLAN 100
Correct. VLAN 100 is within the standard range of 1-1005.
VLAN 0
Why wrong: Incorrect. VLAN 0 is not a valid VLAN number.
VLAN 4095
Why wrong: Incorrect. VLAN 4095 is reserved.
VLAN 1006
Why wrong: Incorrect. VLAN 1006 is an extended VLAN and requires the switch to be in VTP transparent mode or have extended VLAN support enabled.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
VLAN 100
VLAN 100 is a valid VLAN ID because Cisco IOS switches support VLANs in the range 1–1005 for normal-range VLANs, and VLAN 100 falls within this range. Normal-range VLANs are stored in the vlan.dat file and can be created on a standard IOS switch without requiring extended VLAN configuration.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
VLAN 100
Why this is correct
Correct. VLAN 100 is within the standard range of 1-1005.
Related concept
Read the scenario before looking for a memorised answer.
VLAN 0
Why it's wrong here
Incorrect. VLAN 0 is not a valid VLAN number.
VLAN 4095
Why it's wrong here
Incorrect. VLAN 4095 is reserved.
VLAN 1006
Why it's wrong here
Incorrect. VLAN 1006 is an extended VLAN and requires the switch to be in VTP transparent mode or have extended VLAN support enabled.
Common exam traps
Cisco often tests the misconception that any VLAN ID from 1 to 4094 is valid on any switch, but the trap here is that extended VLANs (1006–4094) require specific VTP modes or configuration, and VLANs 0, 1002–1005, and 4095 are reserved or not user-creatable.
Detailed technical explanation
VLANs are identified by a 12-bit field in the IEEE 802.1Q tag, allowing IDs from 0 to 4095, but only IDs 1–1005 are normal-range VLANs stored in vlan.dat, while extended VLANs (1006–4094) require VTP transparent mode or VTPv3 and are stored in the running configuration. VLANs 0 and 4095 are reserved per IEEE 802.1Q standards, and VLANs 1002–1005 are reserved for legacy Token Ring and FDDI networks, so they cannot be created as user-defined VLANs.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A help-desk technician troubleshoots why a newly connected PC cannot reach shared printers on the same floor. The cable is good, the switch port is active, but the PC is in VLAN 20 and the printers are in VLAN 10. The uplink trunk only allows VLAN 10. A trunk being up does not mean every VLAN crosses it.
What to study next
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FAQ
VLANs and Trunking — This question tests VLANs and Trunking — Read the scenario before looking for a memorised answer..
The correct answer is: VLAN 100 — VLAN 100 is a valid VLAN ID because Cisco IOS switches support VLANs in the range 1–1005 for normal-range VLANs, and VLAN 100 falls within this range. Normal-range VLANs are stored in the vlan.dat file and can be created on a standard IOS switch without requiring extended VLAN configuration.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Read the scenario before looking for a memorised answer.
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Last reviewed: Jun 24, 2026
This 350-401 practice question is part of Courseiva's free Cisco 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 350-401 exam.
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