JN0-106 Practice Test 10 — 10 Questions

Question 1

What is the default behavior when a user logs in to a Junos device and enters configuration mode?

Accepted Answer

The user can edit the candidate configuration.. When a user enters configuration mode on a Junos device, they are placed into a private copy of the candidate configuration. This allows the user to make changes without affecting the active configuration until a commit operation is performed. Option B correctly describes this default behavior.

Answer

The user must first commit before making changes.

Answer

The user can only view the configuration.

Answer

The user directly modifies the active configuration.

Question 2

What permission bit must be included in a custom login class to allow a user to execute the ping command?

Accepted Answer

network. Network. In Junos, the 'network' permission bit controls access to network diagnostic commands such as ping, traceroute, and ssh. Without this permission, a user cannot execute these commands even if they have other permissions like view or control.

Answer

view

Answer

control

Answer

system

Question 3

A network engineer needs to verify the checksum of a downloaded Junos image before installation. Which command is used?

Accepted Answer

file checksum sha256 . The `file checksum sha256 ` command computes the SHA-256 hash of the specified file, allowing the engineer to compare it against the published checksum from Juniper Networks to verify integrity and authenticity before installation. This ensures the image has not been corrupted or tampered with during download.

Answer

compare <filename> original

Answer

request system software validate <filename>

Answer

show system software

Question 4

A company uses a Juniper MX router to connect two branch offices via a point-to-point link. The link is flapping. Which command would you use to check the interface errors on the link?

Accepted Answer

show interfaces ge-0/0/0 extensive. The 'show interfaces ge-0/0/0 extensive' command provides detailed interface statistics, including error counters such as CRC errors, frame errors, and link state transitions. This is the most comprehensive command to diagnose why a point-to-point link is flapping, as it reveals physical-layer issues that cause the interface to go up/down repeatedly.

Answer

show log messages

Answer

show configuration interfaces ge-0/0/0

Answer

show interfaces ge-0/0/0 terse

Question 5

A network administrator is troubleshooting high CPU usage on a Juniper router. Which command helps identify which process is consuming the most CPU?

Accepted Answer

show system processes extensive. The 'show system processes extensive' command displays detailed information about all running processes, including CPU utilization, memory usage, and process IDs. This allows the administrator to identify which process (e.g., routing protocol daemon, management daemon) is consuming the most CPU cycles, directly addressing the troubleshooting need.

Answer

show log messages

Answer

show system memory

Answer

show interfaces

Question 6

Refer to the exhibit. An engineer adds a new static route to 10.10.10.0/24 via next-hop 172.16.1.2. The new route does not appear in the route table. What is the most likely reason?

Accepted Answer

The next-hop 172.16.1.2 is not directly reachable.. In Junos, a static route's next-hop must be directly reachable (i.e., on a connected subnet) for the route to be installed in the inet.0 route table. If the next-hop 172.16.1.2 is not directly connected, the route remains hidden (inactive) and does not appear in the forwarding table. Junos does not perform recursive next-hop resolution for static routes by default unless configured with 'resolve'.

Answer

The route requires an export policy to be installed.

Answer

The route has a different AS path.

Answer

Static routes cannot have the same preference as an existing route.

Question 7

An engineer needs to view the current active configuration on a Juniper device. Which command will display the configuration that is currently running?

Accepted Answer

show configuration. The 'show configuration' command displays the current active configuration that is committed and running on a Juniper device. Unlike Cisco's 'show running-config', Junos uses a commit model where the candidate configuration is activated only after a 'commit' operation, and 'show configuration' shows that committed, active configuration.

Answer

show chassis hardware

Answer

show interfaces terse

Answer

show system commit

Question 8

A network administrator wants to view the current configuration that is actively running on a Juniper device. Which operational mode command should be used?

Accepted Answer

show configuration. In Junos OS, the operational mode command 'show configuration' displays the active, committed configuration currently running on the device. Unlike Cisco IOS, Junos does not use a separate 'running-config'; instead, the configuration is stored as a single candidate configuration that becomes active only after a 'commit' operation. Thus, 'show configuration' is the correct command to view the active configuration.

Answer

show running-config

Answer

show active-config

Answer

show current-config

Question 9

An administrator is troubleshooting a configuration issue where a route filter is unexpectedly dropping traffic. The filter uses an 'exact' match type. Which statement correctly describes the behavior of the 'exact' match type in a prefix list?

Accepted Answer

The route must match the prefix and prefix length exactly.. The 'exact' match type in a Junos prefix list requires the route's prefix and prefix length to match the specified prefix and length identically. This is defined in the Junos routing policy framework, where 'exact' is used for precise route filtering, such as matching a specific network like 192.168.1.0/24 without allowing any subnets or supernets.

Answer

The route mask must be equal to or greater than the specified prefix length.

Answer

The prefix 0.0.0.0/0 is never matched by 'exact' filters.

Answer

The route mask must be greater than the specified prefix length.

Question 10

Which TWO statements about the Junos OS configuration hierarchy are correct? (Choose two.)

Accepted Answer

Configuration is organized in a hierarchical structure with levels. Option C is correct because Junos OS stores its configuration in a hierarchical tree structure organized into levels (such as system, interfaces, protocols), which is the defining characteristic of the Junos configuration model. Option E is correct because within that hierarchy, each level can hold one or more statements or values, allowing multiple configuration elements to be nested under a given hierarchy node. Option A is incorrect because Junos does not store configuration as a flat file with line numbers; that describes a line-oriented format, not the Junos hierarchy. Option B is incorrect because the Junos configuration is not assembled by merging multiple configuration files at boot; it is maintained as a single hierarchical candidate/active configuration. Option D is incorrect because inheritance in Junos flows from parent levels down to child levels, not automatically from the root level to all statements.

Answer

All configuration is stored in a flat file with line numbers

Answer

The hierarchy is stored in multiple configuration files that are merged at boot

Answer

Configuration values are inherited from the root level automatically