Juniper Networks Certified Associate, Junos Exam Prep
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Free JNCIA-Junos Practice Questions

10 exam-style questions with answers and explanations, straight from our 1,035-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.

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The JNCIA-Junos exam has 65 questions and runs 1 hour 30 minutes.

These 10 free JNCIA-Junos questions are organized by exam domain, so you can see how each part of the Juniper Networks Certified Associate, Junos blueprint is tested. Reveal the answer and explanation under each question.

Domain 1: Networking Fundamentals

Question 1

A host is assigned the address 172.16.20.75 with a /26 prefix. What is the broadcast address of the subnet in which this host resides?

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Correct answer: B - 172.16.20.127

Question 2

An eight-port Layer 2 switch has all of its ports assigned to a single VLAN. How many collision domains and broadcast domains does the switch create?

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Correct answer: C - 8 collision domains and 1 broadcast domain

Question 3

During encapsulation in the TCP/IP model, what is the name of the protocol data unit (PDU) at the Transport layer when TCP is used?

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Correct answer: C - Segment

Domain 2: Junos OS Fundamentals

Question 4

A remote host sends an ICMP echo request (ping) to the loopback address of a Junos device. How is this traffic classified and handled?

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Correct answer: B - Exception traffic, sent to the Routing Engine and rate-limited to protect the control plane

Question 5

The Routing Engine of a Junos router becomes heavily loaded during a large routing protocol reconvergence. What happens to existing transit traffic already flowing through the device?

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Correct answer: A - It continues to be forwarded by the Packet Forwarding Engine using its local copy of the forwarding table

Domain 3: User Interfaces

Question 6

An engineer has made several uncommitted changes in configuration mode and now wants to discard ALL of them so the candidate configuration once again matches the active configuration. Which command does this?

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Correct answer: C - rollback 0

Question 7

An administrator activates a configuration with the 'commit confirmed' command and then enters no further commands. Assuming default settings, what happens?

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Correct answer: D - The device reverts to the previous configuration when the default confirmation timer expires

Domain 4: Configuration Basics

Question 8

On a Junos device, a physical interface is named ge-1/2/3. What does the '2' in this interface name represent?

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Correct answer: C - The PIC (Physical Interface Card) slot number

Question 9

A Junos device has been reset to its factory-default configuration. An engineer configures the hostname and a management IP address, then issues a commit, but the commit fails. What is the MOST likely cause?

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Correct answer: A - The root authentication (root password) has not been set

Question 10

Which predefined Junos login class allows a user to view the operational state of the device but NOT to modify the configuration or issue clear, restart, or reset commands?

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Correct answer: B - read-only

The rest of the JNCIA-Junos blueprint

The JNCIA-Junos exam also covers these domains. Drill them in the full free practice test:

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