JN0-106 Multiple Select — 50 Questions

Question 1

Which THREE route types are considered protocol-independent in Junos?

Accepted Answer

Direct routes. Direct, local, and static routes are considered protocol-independent because they are not learned or installed by any dynamic routing protocol. Direct routes are automatically created for directly connected interfaces, local routes represent the interface's own IP address, and static routes are manually configured by an administrator. These routes exist in the routing table regardless of whether any routing protocol is running, hence the term 'protocol-independent'.

Answer

BGP routes

Answer

OSPF routes

Question 2

Which TWO statements about the Junos CLI are correct?

Accepted Answer

The pipe character (|) can be used to filter command output.. Option B is correct because the pipe character (|) in the Junos CLI is used to filter or manipulate the output of show commands, for example with match, except, find, count, or display set. Option C is correct because from configuration mode the run command (or its abbreviation run) executes operational mode commands without leaving configuration mode, e.g., run show interfaces terse. Option A is incorrect because commit confirmed applies the candidate configuration temporarily and automatically rolls back after 10 minutes unless confirmed with a second commit, so it does not save permanently. Option D is incorrect because set cli screen-length 0 disables paging of output, not command-line editing features. Option E is incorrect because rollback 0 loads the currently active committed configuration, while rollback 1 reverts to the previous committed configuration.

Answer

The `commit confirmed` command saves the configuration permanently.

Answer

The `set cli screen-length 0` command disables command-line editing features.

Answer

The `rollback 0` command reverts to the previous committed configuration.

Question 3

Which TWO commands can be used to view the current operational state of an interface? (Choose two.)

Accepted Answer

show interfaces extensive. The 'show interfaces extensive' command displays detailed operational state information, including current status, errors, and statistics. The 'show interfaces terse' command provides a concise operational view showing interface names, administrative status, link status, and protocol families. Both commands query the current operational state of interfaces from the Junos OS kernel.

Answer

show log

Answer

show configuration interfaces

Answer

show route

Question 4

Which TWO commands can be used to view the current routing table entries for IPv4 unicast routes?

Accepted Answer

show route table inet.0. `show route table inet.0` explicitly displays the IPv4 unicast routing table (inet.0) in Junos. Option D is correct because `show route` without any filter defaults to showing all routes in the inet.0 table, which is the primary IPv4 unicast routing table.

Answer

show route protocol static

Answer

show forwarding-table

Answer

show route table inet6.0

Question 5

Which two commands display the IPv4 unicast routing table? (Choose two.)

Accepted Answer

show route. Option C, `show route`, is correct because on Junos devices this command displays the complete routing table, which by default is the IPv4 unicast table (inet.0), listing all learned and direct routes. Option D, `show route table inet.0`, is also correct because inet.0 is the specific routing table name for IPv4 unicast routes, so this command explicitly displays exactly that table. Option A, `show ip route`, is not a valid Junos command (it is Cisco IOS syntax), so it does not belong. Option B, `show route protocol ospf`, only filters and displays OSPF-learned routes rather than the entire IPv4 unicast routing table. Option E, `show routing`, is not a valid command and therefore cannot display the routing table.

Answer

show ip route

Answer

show route protocol ospf

Answer

show routing

Question 6

Which THREE statements correctly describe the behavior of the 'replace pattern' command in Junos configuration mode?

Accepted Answer

It can be used to change interface names or IP addresses throughout the configuration.. Option C is correct because the 'replace pattern' command performs a global find-and-replace across the candidate configuration, making it ideal for renaming interfaces or changing IP addresses everywhere they appear. Option D is correct because 'replace pattern' edits the candidate configuration, not the active configuration, so changes must still be committed to take effect. Option E is correct because the command matches text using regular expressions (e.g., 'replace pattern ge-0/0/0 with ge-0/0/1'), allowing flexible pattern-based substitutions. Option A is not correct because 'replace pattern' does not itself validate the replacement for correctness before applying; validation occurs at commit time via 'commit check' or the commit process. Option B is not correct because 'replace pattern' does not automatically commit changes; the user must explicitly issue a 'commit' command afterward.

Answer

It validates the replacement configuration for correctness before applying.

Answer

It automatically commits the changes after replacement.

Question 7

Which two commands can be used to display real-time interface information? (Choose two.)

Accepted Answer

monitor interface. Option A, `monitor interface`, is correct because it provides a real-time, continuously updating view of interface statistics such as traffic counters, errors, and link state on Juniper devices. Option B, `monitor traffic`, is correct because it captures and displays live packet-level traffic on an interface, showing real-time data as packets traverse the interface. Option C, `show log`, is incorrect because it displays stored log file contents rather than live interface information. Option D, `request system reboot`, is incorrect because it reboots the device and does not display interface data. Option E, `show system storage`, is incorrect because it reports disk and filesystem usage, not real-time interface information.

Answer

show log

Answer

request system reboot

Answer

show system storage

Question 8

Which THREE actions can be performed in operational mode on a Junos device?

Accepted Answer

Ping a remote host. In Junos, operational mode is the CLI mode entered after login (prompt user@host>), used for monitoring and controlling device state. Option B (Ping a remote host) is correct because the ping command is an operational-mode command used to test reachability to a remote host. Option D (View system logs) is correct because operational mode provides commands such as show log messages to inspect system log files. Option E (Reboot the chassis) is correct because the request system reboot command is executed from operational mode to restart the device. Options A and C are not operational-mode actions: committing configuration changes (commit) and configuring interface IP addresses (set interfaces ...) are performed in configuration mode, which is entered with the configure command.

Answer

Commit configuration changes

Answer

Configure interface IP addresses

Question 9

Which TWO statements about the rescue configuration are correct? (Choose two.)

Accepted Answer

The rescue configuration is designed to provide a method of last-resort recovery.. Option C is correct because the rescue configuration exists specifically as a last-resort recovery mechanism, allowing an administrator to return a device to a known-good configuration when the active configuration is broken or inaccessible. Option D is correct because on Junos devices the rescue configuration is created and stored by running the operational-mode command 'request system configuration rescue save', which snapshots the current candidate configuration as the rescue configuration. Option A is wrong because the rescue configuration is not saved automatically on every commit; it must be saved explicitly by the administrator. Option B is wrong because 'rollback rescue' loads the previously saved rescue configuration, not the factory-default configuration, which would be loaded with 'load factory-default' or 'rollback 0' depending on context. Option E is wrong because the rescue configuration restores the entire saved configuration, not just a subset of it.

Answer

The rescue configuration is automatically saved after every commit.

Answer

The 'rollback rescue' command loads the factory-default configuration.

Answer

The rescue configuration can be used to restore only a subset of the configuration.

Question 10

Which THREE of the following are characteristics of configuration groups in Junos?

Accepted Answer

The 'apply-groups' statement is used to specify which group(s) should be inherited.. Option A is correct because Junos uses the 'apply-groups' statement (and 'apply-groups-except') to specify which configuration group(s) a given hierarchy level should inherit from. Option C is correct because Junos configuration groups support nesting: a group can itself contain an 'apply-groups' statement, allowing one group to inherit from another group. Option D is correct because the core purpose of configuration groups is to define a reusable set of configuration statements once and have them inherited by multiple sections of the configuration, reducing duplication. Option B is incorrect because there is no limit of 10 groups per statement; Junos allows up to 50 groups to be applied at a single hierarchy level. Option E is incorrect because statements inherited from a group can be overridden by explicitly configuring the same statement in the main configuration, which takes precedence over the inherited value.

Answer

A maximum of 10 groups can be applied to a single configuration statement.

Answer

Configuration groups do not allow individual statements within the group to be overridden in the main configuration.

Question 11

Which two statements correctly describe Junos OS login classes? (Choose two.)

Accepted Answer

They are defined under the [edit system login class] hierarchy.. Option B is correct because login classes are configured at the [edit system login class class-name] hierarchy in Junos OS, where you define permissions and other login parameters. Option D is correct because a login class can include or exclude the configure permission, thereby restricting whether a user can enter configuration mode. Options A, C, and E are incorrect: login classes do not force operational-mode-only access (that depends on permissions such as configure), they are not automatically assigned to all users by default (each user must be associated with a class, otherwise the default class applies), and they can be modified or deleted after creation.

Answer

They allow users to enter only operational mode.

Answer

They are automatically assigned to all users by default.

Answer

They cannot be modified after creation.

Question 12

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

Question 13

Which two events typically trigger a change to the routing table? (Choose two.)

Accepted Answer

Interface state change. An interface state change (up/down) directly affects the reachability of directly connected networks. When an interface goes up, Junos adds the corresponding directly connected route to the routing table; when it goes down, the route is removed. Similarly, a BGP neighbor reset causes the BGP session to be torn down and re-established, which triggers the withdrawal and re-advertisement of all BGP routes, thereby modifying the routing table.

Answer

System uptime

Answer

Log file rotation

Answer

Configuration commit

Question 14

Which TWO statements about route preferences in Junos are correct?

Accepted Answer

Direct routes have a default preference of 0.. In Junos, direct (connected) routes have a default route preference of 0, which is the highest possible preference, ensuring they are always preferred over other route types for directly attached networks. Option C is correct because OSPF internal routes (both intra-area and inter-area) have a default preference of 10 in Junos, which is lower than most other dynamic routing protocols, making OSPF routes more preferred by default.

Answer

The preference of a route cannot be changed.

Answer

Static routes have a default preference of 10.

Answer

BGP routes have a default preference of 200.

Question 15

Which two commands can be used to monitor real-time interface statistics and errors on a Junos device?

Accepted Answer

show interfaces extensive ge-0/0/0 | refresh 1. Option C, 'show interfaces extensive ge-0/0/0 | refresh 1', is correct because the 'extensive' keyword displays detailed statistics including error counters, and the '| refresh 1' pipe re-runs the command every second, giving real-time monitoring of a specific interface. Option D, 'monitor interface ge-0/0/0', is correct because the 'monitor interface' command is Junos's dedicated real-time interface statistics viewer, continuously updating counters such as packets, bytes, and errors for the named interface. Option A, 'show interfaces terse', only gives a one-time summary of interface status and addresses without error detail or refresh, so it is not real-time monitoring. Option B, 'show interfaces ge-0/0/0', provides a single snapshot of standard statistics and does not refresh or emphasize error counters. Option E, 'monitor security log', streams security log messages rather than interface statistics and errors, so it does not meet the requirement.

Answer

show interfaces terse

Answer

show interfaces ge-0/0/0

Answer

monitor security log

Question 16

Which TWO statements about configuration archival in Junos are true?

Accepted Answer

The 'system archival' hierarchy enables automatic backup of configurations.. The 'system archival' hierarchy in Junos is specifically designed to enable automatic backup of configuration files. This feature allows administrators to configure periodic transfers of committed configurations to a remote server, ensuring configuration history is preserved without manual intervention.

Answer

Archival stores the candidate configuration.

Answer

Archival only saves the rescue configuration.

Answer

Archival automatically archives after every commit without any configuration.

Question 17

Which two statements are true about static routes on Juniper devices? (Choose two.)

Accepted Answer

A static route with a next-hop of an IP address requires that the next-hop be reachable.. Option A is correct because a static route whose next-hop is specified as an IP address is only installed in the routing table (and thus active) if that next-hop is resolvable and reachable via a route in inet.0; if the next-hop is unreachable, the route stays hidden. Option B is correct because Junos supports the qualified-next-hop statement, which lets you attach a separate preference to each next-hop of a static route, enabling conditional/backup routing where the secondary next-hop is used only when the primary becomes unreachable. Option C is wrong because a static route pointing at an interface (e.g., next-hop ge-0/0/0.0) is only active while that interface is up, so it is not active when the interface is down. Option D is wrong because in Junos a lower preference value is preferred, so a route with preference 5 wins over one with preference 10. Option E is wrong because static routes can perform load balancing by configuring multiple next-hops (or multiple paths) for the same destination, which are then installed as equal-cost multipath entries.

Answer

A static route with a next-hop of an interface will be active even if the interface is down.

Answer

A static route with a preference of 10 is preferred over a static route with a preference of 5.

Answer

Static routes cannot be used for load balancing.

Question 18

Which TWO configuration statements are valid for defining a static route on a Junos device?

Accepted Answer

set routing-options static route 10.0.0.0/8 discard. Option A is correct because Junos supports the discard next-hop on a static route, which silently drops matching traffic and is configured exactly as set routing-options static route 10.0.0.0/8 discard. Option C is correct because qualified-next-hop is a valid Junos static-route next-hop type that allows a per-next-hop preference, so set routing-options static route 10.0.0.0/8 qualified-next-hop 192.168.1.1 preference 10 is syntactically valid. Option B is wrong because reject-all is not a valid Junos static-route next-hop keyword; the valid reject form is simply reject. Option D is wrong because Junos static routes do not use a metric statement; route preference is set with preference, not metric. Option E is wrong because passive is not a valid static-route option in Junos.

Answer

set routing-options static route 10.0.0.0/8 reject-all

Answer

set routing-options static route 10.0.0.0/8 next-hop 192.168.1.1 metric 10

Answer

set routing-options static route 10.0.0.0/8 passive

Question 19

Which TWO factors are directly used when comparing route preferences in JunOS? (Choose two.)

Accepted Answer

Metric (or cost). In Junos, route preference (also called administrative distance) is the primary tie-breaker used to compare routes from different protocols, so option E (Preference value) is directly used — lower preference wins, e.g., direct=0, static=5, OSPF internal=10, RIP=100. When two routes come from the same protocol, the protocol's metric/cost is compared, so option C (Metric or cost) is also directly used, e.g., OSPF cost or RIP hop count. Option A (Next-hop reachability) is a validity condition for installing a route, not a comparison factor between competing routes. Option B (Number of hops) is only a metric within protocols like RIP, not a universal Junos comparison factor. Option D (Prefix length) is used for longest-match forwarding lookups in the forwarding table, not for route preference comparison in the routing table.

Answer

Next-hop reachability

Answer

Number of hops

Answer

Prefix length

Question 20

Which TWO statements are true about commit operations in Junos? (Choose two.)

Accepted Answer

The commit command requires the candidate configuration to be syntactically correct.. Option B is correct because the commit command validates the candidate configuration for syntax and semantic errors before merging it into the active configuration; if the candidate is not syntactically correct, the commit fails and the running configuration remains unchanged. Option C is correct because commit confirmed activates the candidate configuration on a trial basis and, if the operator does not issue a confirming commit within the default 10-minute window, Junos automatically rolls back to the previously active configuration. Option A is wrong because rollback 0 loads the last committed (active) configuration into the candidate, it does not reboot the device. Option D is wrong because commit check only validates the candidate configuration for syntax and commit-time errors without applying it to the running system. Option E is wrong because commit at schedules a configuration commit at a specified time, not a system reboot.

Answer

The rollback 0 command will cause a system reboot.

Answer

The commit check command applies the configuration to the running system.

Answer

The commit at command is used to schedule a system reboot.