JN0-106 Multiple Select — 10 Questions

Question 1

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. The 'show interfaces extensive ge-0/0/0 | refresh 1' command displays detailed interface statistics and errors, and the 'refresh 1' pipe modifier automatically updates the output every second, enabling real-time monitoring. Option D is correct because the 'monitor interface ge-0/0/0' command is specifically designed for real-time monitoring of interface counters and errors, refreshing the display at a default interval of 1 second. Both commands provide live views of interface statistics such as input/output packets, errors, drops, and CRC errors.

Answer

show interfaces terse

Answer

show interfaces ge-0/0/0

Answer

monitor security log

Question 2

Which TWO statements are true about the Junos file system? (Choose two.)

Accepted Answer

The /config directory contains configuration files.. The /config directory in the Junos file system stores the active and backup configuration files, including juniper.conf and juniper.conf.gz. These files are critical for device operation and are loaded during the boot process.

Answer

The /altroot directory is a backup root filesystem.

Answer

The /kernel directory contains the operating system kernel.

Answer

The root directory (/) is a RAM disk.

Question 3

Which TWO commands can be used to view the system log messages on a Juniper device? (Select two.)

Accepted Answer

show log messages. 'show log messages' displays the contents of the default system log file, /var/log/messages, which contains kernel, daemon, and system-level messages. Option C is correct because 'monitor start messages' provides a real-time tail of the same /var/log/messages file, allowing live monitoring of system log entries as they are written.

Answer

show log dcd

Answer

show log file

Answer

show system messages

Question 4

Which THREE statements are true about commit operations in Junos OS?

Accepted Answer

Multiple users can make configuration changes simultaneously, but only one can commit at a time.. Junos OS allows multiple users to enter configuration mode and make changes simultaneously, but the commit operation is serialized: only one user can commit at a time. This prevents conflicting changes from being applied concurrently, ensuring configuration consistency.

Answer

The 'commit confirmed' command immediately discards changes if not confirmed.

Answer

The 'commit' command always requires 'commit synchronize' when using dual Routing Engines.

Question 5

Which two statements about static routes in Junos OS are correct?

Accepted Answer

Static routes have a default preference of 5.. Static routes have a default preference of 5 in Junos OS. Option C is correct: when a static route uses an interface as the next-hop (e.g., ge-0/0/0), the router uses ARP to resolve the MAC address of the next-hop device. Option D is correct: a static route with a next-hop of 0.0.0.0 is a discard route that silently drops packets. Option A is incorrect: a static route with a next-hop of 127.0.0.1 creates a reject route (sends ICMP unreachable), not an unreachable route. Option E is incorrect: static routes cannot have a preference value of 0 because preference 0 is reserved for directly connected routes.

Answer

A static route with a next-hop of 127.0.0.1 is an unreachable route.

Answer

Static routes can have a preference value of 0.

Question 6

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 7

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 8

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 9

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 10

Which THREE modes can be used to enter configuration mode in Junos? (Choose three.)

Accepted Answer

configure private. 'configure private' creates a private configuration session that isolates candidate changes from other users, allowing multiple users to stage changes simultaneously without interference. This mode is one of the three standard configuration modes in Junos, alongside exclusive and shared.

Answer

configure static

Answer

configure dynamic