JN0-106 Practice Test 7 — 10 Questions

Question 1

Refer to the exhibit. A host connected to ge-0/0/1 cannot reach a host connected to ge-0/0/2 even though both are in VLAN10. What is the most likely cause?

Accepted Answer

The hosts are configured with IP addresses on different subnets.. Although both hosts are in the same VLAN and can communicate at Layer 2 (MAC addresses), IP communication requires them to be on the same IP subnet. If the hosts have IP addresses on different subnets, they will attempt to use a default gateway for routing. Without a router or IRB interface configured, the traffic cannot be delivered, leading to unreachability.

Answer

VLAN10 is not defined in the global VLAN configuration.

Answer

An IRB interface for VLAN10 is not configured.

Answer

The interface ge-0/0/2 is configured as a trunk port.

Question 2

A network engineer configures a static route to 10.0.0.0/8 with a preference of 20. An OSPF internal route to 10.0.0.0/8 has a default preference of 10. Which route will be active in the routing table?

Accepted Answer

The OSPF route, because of lower preference.. In Junos, the active route in the routing table is determined by the lowest preference value. OSPF internal routes have a default preference of 10, while static routes have a default preference of 5, but here the static route is configured with a preference of 20. Since OSPF's preference (10) is lower than the static route's preference (20), the OSPF route is chosen as active.

Answer

Both routes, because they have different protocols.

Answer

Neither, because of a conflict.

Answer

The static route, because it is manually configured.

Question 3

An engineer needs to apply a configuration change that adds a new static route to the Junos device. The engineer wants to ensure the change takes effect immediately and is persistent across reboots. Which command should the engineer use?

Accepted Answer

commit. The 'commit' command is correct because it immediately activates the candidate configuration (including the new static route) and makes it the active configuration that survives a reboot. Junos uses a two-stage configuration model where changes are first made to the candidate configuration and then committed to become the active, persistent configuration.

Answer

load override

Answer

commit confirmed

Answer

rollback

Question 4

A network administrator needs to temporarily disable a set of configuration statements for testing without deleting them. Which approach should be used?

Accepted Answer

use the 'deactivate' command to mark the statements inactive. The 'deactivate' command in Junos allows an administrator to temporarily disable a set of configuration statements without removing them from the configuration. When a statement is deactivated, it is prefixed with 'inactive:' in the configuration hierarchy, and the commit operation ignores it. This is ideal for testing changes, as the statements can be easily re-enabled using the 'activate' command.

Answer

delete the statements and later re-add from a backup

Answer

comment out the lines using #

Answer

set the configuration to a different group and remove apply-groups

Question 5

A network engineer is designing a redundant network with two Juniper routers running VRRP. The virtual IP address is 10.0.0.1. Both routers are configured as VRRP group 1. What is the purpose of the 'priority' parameter in VRRP configuration?

Accepted Answer

It determines the master router election.. In VRRP, the 'priority' parameter (range 1-254, default 100) is used to elect the master router. The router with the highest priority becomes the master for the virtual IP address 10.0.0.1, ensuring redundancy by taking over traffic forwarding if the current master fails.

Answer

It sets the interval for VRRP advertisements.

Answer

It determines the virtual MAC address.

Answer

It changes the virtual IP address.

Question 6

An engineer notices that a Juniper device is not saving configuration changes across reboots. What is the most likely cause?

Accepted Answer

The candidate configuration was not committed.. In Junos OS, configuration changes are stored in a candidate configuration and only become active and persistent across reboots after a 'commit' operation. Without a commit, the changes remain in the candidate buffer and are discarded upon reboot, causing the device to revert to the last committed configuration.

Answer

The rescue configuration is not set.

Answer

The device is booting from factory-default configuration.

Answer

The command 'request system reboot' was used instead of 'commit'.

Question 7

An engineer wants to apply a candidate configuration and automatically revert to the previous configuration after 10 minutes if the commit is not confirmed. Which command should be used?

Accepted Answer

commit confirmed 10. The `commit confirmed 10` command commits the candidate configuration and starts a 10-minute timer. If the commit is not explicitly confirmed with another `commit` command within that time, Junos automatically reverts to the previous configuration. This is the correct method for a timed automatic rollback after a commit.

Answer

commit at 10

Answer

set system commit timer 10

Answer

commit check

Question 8

A network engineer configures a static route to a remote network. They want the route to be automatically removed from the routing table if the directly connected interface used to reach the next hop fails. Which configuration approach should be used?

Accepted Answer

Configure the next-hop as the interface name.. Configuring the next-hop as an interface name (e.g., ge-0/0/0) creates a static route that is automatically removed from the routing table when that interface goes down. This is due to the route being 'qualified' by the interface's operational state; if the interface fails, the route is withdrawn. In contrast, using an IP address as the next-hop does not tie the route to the interface's state, so the route remains even if the interface fails, as long as the next-hop is reachable via another path.

Answer

Configure a higher metric on the static route.

Answer

Configure a preference of 0 on the static route.

Answer

Configure the next-hop as an IP address.

Question 9

Which command is used to verify that the current active configuration is the same as the candidate configuration?

Accepted Answer

show | compare. The command `show | compare` displays the differences between the candidate configuration and the active (committed) configuration. If there are no differences, the candidate configuration is identical to the active configuration. This is the correct way to verify whether the candidate configuration matches the active configuration in Junos.

Answer

commit check

Answer

show configuration

Answer

show system configuration

Question 10

A router has two routes to the same destination: one with preference 10 and metric 5, and another with preference 15 and metric 3. Which route will be installed in the forwarding table?

Accepted Answer

The route with preference 10.. In Junos, the route preference (administrative distance) is the primary criterion for selecting the best route to a destination. The route with preference 10 is preferred over the route with preference 15, regardless of metric values. The route with preference 10 is installed in the forwarding table.

Answer

The route with metric 3.

Answer

Neither route is installed.

Answer

Both routes are installed if ECMP is enabled.