• 65 questions

Juniper JNCIA Practice Test

Questions for JNCIA-Junos exam JN0-106, each answer linked to the Juniper documentation page or RFC behind it.

Which kind of address does IPv6 not have?

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Exam mode: 65 questions, 90 minutes.

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Unofficial practice questions, not affiliated with Juniper Networks, Inc. or Hewlett Packard Enterprise. Bank checked October 9, 2026.

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All 65 questions

Networking fundamentals 9

  • A frame arrives for a destination MAC address that is not in the Ethernet switching table. What does the switch do with it? Ethernet Switching User Guide, Bridging and VLANs, How Bridging of VLAN Traffic Works
  • A host needs the Ethernet address that goes with an IP address on its own LAN. How is the ARP request delivered? RFC 826, Packet Generation
  • A switch carries VLAN 10 and VLAN 20. A host in VLAN 10 sends a broadcast frame. Which hosts receive it? Ethernet Switching User Guide, Bridging and VLANs, History of VLANs
  • From which part of a frame does a switch learn the entries of its Ethernet switching table? Ethernet Switching User Guide, Bridging and VLANs, How Bridging of VLAN Traffic Works
  • In Junos class of service, what does a classifier associate each incoming packet with? Class of Service User Guide for Routers, Junos CoS Components Used to Manage Congestion and Control Service Levels
  • The mask of a /22 prefix is 255.255.252.0. What is the third octet, 252, written as eight binary digits? RFC 4632, section 6.1
  • Which kind of address does IPv6 not have? RFC 4291, section 2
  • Which of these is a correct short form of the IPv6 address 2001:0db8:0000:0000:0000:0000:0000:0001? RFC 4291, section 2.2
  • Which single prefix covers exactly the four networks 192.168.4.0/24, 192.168.5.0/24, 192.168.6.0/24 and 192.168.7.0/24? RFC 4632, sections 3.1 and 6.1
Show all 65 questions (56 more)

Junos OS fundamentals 9

  • A packet passes through the router on its way from one host to another. Which element handles that transit traffic? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Router Data Flow Overview, Flow of Data Packets
  • A Telnet session is opened to the router itself. Which element receives these local packets? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Router Data Flow Overview, Flow of Local Packets
  • An OSPF hello packet arrives from a neighbor. Which component handles it? Overview for Junos OS, Junos OS Architecture Overview, Routing Engine
  • One Junos software process fails. Why does that usually leave the other processes running? Overview for Junos OS, Junos OS Architecture Overview, Routing Engine
  • The Routing Engine installs a changed forwarding table. What happens to packet forwarding while the table is updated? Overview for Junos OS, Junos OS Architecture Overview, Routing Engine
  • Where does the Packet Forwarding Engine get its forwarding table? Overview for Junos OS, Junos OS Architecture Overview, Routing Engine
  • Which Junos process manages the configuration and all user commands, and tells other processes that a new configuration has been committed? Overview for Junos OS, Junos OS Routing Engine Components and Processes, Management Process
  • Which Junos process starts the configured routing protocols and maintains the routing tables? Overview for Junos OS, Junos OS Routing Engine Components and Processes, Routing Protocol Process
  • Which part of a Junos router performs route lookups and forwards packets between input and output interfaces? Overview for Junos OS, Junos OS Architecture Overview, Packet Forwarding Engine

User interfaces 10

  • The prompt in the CLI goes from user@host> to user@host#. What does the # show? CLI User Guide for Junos OS, Getting Started: A Quick Tour of the CLI
  • Which command prints only a number, the count of lines in the active configuration? CLI User Guide for Junos OS, Filtering Operational Command Output
  • Which configuration mode command shows the configuration as the series of set commands that would create it? CLI User Guide for Junos OS, View the Configuration, Display set Commands from the Configuration
  • Which form of the configure command locks the candidate configuration until you leave configuration mode? CLI User Guide for Junos OS, Overview of the Configure Command, How to Use the configure exclusive Command
  • You are in configuration mode and want to see the output of show interfaces terse without leaving it. What do you type? CLI User Guide for Junos OS, CLI Configuration Mode Overview
  • You cannot recall a command name but know it has to do with ospf. Which command lists the commands and help text that contain that string? CLI User Guide for Junos OS, Online Help in the CLI
  • You enter configuration mode and change a statement. Which configuration have you changed so far? CLI User Guide for Junos OS, CLI Overview
  • You load a saved file with load override. What happens to the candidate configuration? CLI User Guide for Junos OS, Loading Configuration Files
  • You run commit confirmed with no number, and your session then drops. What does the device do? CLI User Guide for Junos OS, Commit the Configuration, Activate a Device Configuration with Confirmation
  • You type rollback 1 in configuration mode and see load complete. What is still needed before the device runs that configuration? CLI User Guide for Junos OS, Managing Configurations

Configuration basics 10

  • A new device is switched on for the first time. How do you log in? User Access and Authentication Administration Guide for Junos OS, Root Password
  • How many login classes can be assigned to one user account? User Access and Authentication Administration Guide for Junos OS, Login Classes Overview
  • In Junos, what is a logical interface, also known as a unit? Interfaces Fundamentals for Junos OS, Logical Interfaces
  • What is the Network Time Protocol used for on a Junos device? Timing and Synchronization Guide, Network Time Protocol
  • Where does Junos OS place the files produced by tracing and logging operations? Overview for Junos OS, Tracing and Logging Junos OS Operations
  • Which command makes the last committed configuration the rescue configuration? CLI User Guide for Junos OS, Rescue Configuration
  • Which predefined login class has the view permission flag and nothing else? User Access and Authentication Administration Guide for Junos OS, Login Classes Overview, Predefined System Login Classes
  • Which three methods of user authentication does Junos OS support? User Access and Authentication Administration Guide for Junos OS, User Authentication Overview, User Authentication Methods
  • You run load factory-default on a switch. What does the procedure tell you to configure before you commit? CLI User Guide for Junos OS, Factory Default Configuration Overview, Restore the Default Factory Configuration
  • You want the device to send its configuration to an archive site each time a commit is made. Which statement under system archival configuration does that? CLI User Guide for Junos OS, Back Up Configurations to an Archive Site

Operational monitoring and maintenance 9

  • Before an upgrade, which option of request system software add checks the new software against the current configuration? Junos OS Software Installation and Upgrade Guide, Junos OS Installation and Upgrade Overview
  • The root password is lost. What kind of access do you need to recover it? User Access and Authentication Administration Guide for Junos OS, Recover a Root Password
  • What does the monitor traffic command display? Junos CLI Reference, monitor traffic, Description
  • Which command frees storage space by rotating the log files and suggesting files that could be deleted? Junos CLI Reference, request system storage cleanup, Description
  • Which command gives a summary of the interfaces, one line each? Junos CLI Reference, show interfaces terse, Description
  • Which command shows real-time statistics for an interface and updates them every second? Junos CLI Reference, monitor interface, Description
  • Which operational command shows the route that packets take to a host, and so helps locate a point of failure? Junos CLI Reference, traceroute, Description
  • You installed a new release with request system software add. What must happen before the device runs it? Junos OS Software Installation and Upgrade Guide, Installing Software on Routing Devices
  • You must shut the device software down cleanly before pulling the power cord. Which command stops the device software? Junos CLI Reference, request system halt, Description

Routing fundamentals 9

  • A device learns 10.1.0.0/16 both as a static route and as an OSPF internal route. With default preferences, which one becomes active? Routing Protocols Overview, Understanding Route Preference Values (Administrative Distance)
  • How do the routing table and the forwarding table differ? Routing Protocols Overview, Routing Databases Overview
  • What does the show route command display when it is given no options? Junos CLI Reference, show route, Description
  • What is the default preference of a directly connected network? Routing Protocols Overview, Understanding Route Preference Values (Administrative Distance)
  • What is the default route preference of a route learned from BGP in Junos OS? Routing Protocols Overview, Understanding Route Preference Values (Administrative Distance)
  • When is a static route placed in the forwarding table? Protocol-Independent Routing Properties User Guide, Configure Static Routes, Understand Basic Static Routing
  • Which routing table holds IPv4 unicast routes by default? Protocol-Independent Routing Properties User Guide, Configuring Junos OS Routing Tables
  • Which statement sets a static default route toward the gateway 172.16.1.1? Protocol-Independent Routing Properties User Guide, Configure Static Routes
  • You create a routing instance named CUST-A. What is its IPv4 unicast routing table called? Routing Protocols Overview, Routing Instances Overview

Routing policy and firewall filters 9

  • A packet is tested against a firewall filter and matches none of its terms. What happens to the packet? Routing Policies, Firewall Filters, and Traffic Policers User Guide, How Standard Firewall Filters Evaluate Packets
  • A route is tested against a routing policy and matches none of its terms. What happens to the route? Routing Policies, Firewall Filters, and Traffic Policers User Guide, How a Routing Policy Is Evaluated
  • A route matches the first term of a policy, and the term's action is accept. What happens to the later terms? Routing Policies, Firewall Filters, and Traffic Policers User Guide, How a Routing Policy Is Evaluated
  • The from statement of a policy term lists two match conditions. When does a route match the term? Routing Policies, Firewall Filters, and Traffic Policers User Guide, How a Routing Policy Is Evaluated
  • In a route filter, what does the match type orlonger match for the prefix 10.0.0.0/8? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Understanding Route Filters for Use in Routing Policy Match Conditions
  • RIP is running and no export policy is configured. Which routes does RIP advertise from the routing table? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Default Routing Policies
  • What is another name for a stateless firewall filter? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Router Data Flow Overview, Stateless and Stateful Firewall Filters
  • Which kind of traffic does a firewall filter applied to the loopback interface lo0 control? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Router Data Flow Overview, Flow of Local Packets
  • With no export policy configured, which routes does BGP advertise to its peers? Routing Policies, Firewall Filters, and Traffic Policers User Guide, Default Routing Policies

How this list was compiled: Own questions, written to the seven exam objectives that Juniper lists for the Junos, Associate (JNCIA-Junos) exam JN0-106. The address https://www.juniper.net/us/en/training/certification/tracks/junos/jncia-junos.html led on 2026-10-09 to the certification overview at https://learningportal.juniper.net/juniper/user_activity_info.aspx?id=14354, where the objectives and the exam details were read. Facts were read on 2026-10-09 in Juniper's public documentation at www.juniper.net/documentation (the CLI User Guide, the Overview for Junos OS, the routing, routing policy, interface, user access, installation and class of service guides and the Junos CLI Reference) and in RFC 826, RFC 4291 and RFC 4632 at rfc-editor.org. Each question names the page and section it was written from and links to it. Licence: Own work. Every question, wrong choice and explanation was written for this site from the public documentation and RFCs named in each question. Nothing is copied or reworded from a Juniper exam, Juniper's practice exams, a course or another practice product.

How it works

An unofficial JNCIA-Junos practice test: 65 of our own questions, sorted by the seven exam objectives Juniper lists for JN0-106. This site is not affiliated with Juniper Networks or Hewlett Packard Enterprise, and nothing here comes from the real exam or Juniper's practice exams.

Read the full guide

What the JNCIA-Junos exam asks

Juniper's certification page, read on October 9, 2026, lists seven objectives for exam JN0-106: networking fundamentals, Junos OS fundamentals, user interfaces, configuration basics, operational monitoring and maintenance, routing fundamentals, and routing policy and firewall filters. It gives no weights, so each has 9 or 10 questions here.

Which Junos version, and what is left out

The exam details name Junos OS 21.2. The answers follow the current Junos documentation, where a default can differ between releases. J-Web, SNMP, configuration groups, unicast reverse-path forwarding and firewall filter match conditions are not asked.

  • The lower route preference wins: direct 0, static 5, OSPF internal 10, RIP 100, BGP 170.
  • rollback only loads a configuration into the candidate. Nothing changes on the device until you commit.
  • A route that matches no policy term gets the default policy. A packet that matches no firewall filter term is discarded.

Questions and answers

How many questions are on the JNCIA-Junos exam?

65 multiple-choice questions in 90 minutes, by Juniper's certification page, which gives the exam code JN0-106. Exam mode here sets all 65 of our questions against a 90-minute clock.

What is the passing score for JNCIA-Junos?

Juniper's page publishes none. It says pass or fail status is available immediately after the exam. A result on this page shows your percent right for each objective and no pass or fail.

How long is the JNCIA-Junos certification valid?

Three years, by Juniper's certification page, which lists no prerequisite certification. The page says the exam is provided in English only.

Is this JNCIA practice test free?

Yes. Every question, every explanation with its source link and the timed exam mode are free, with no sign-up.

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