JN0-106 Operational Monitoring and Maintenance — 10 Questions

Question 1

A network engineer notices that a device is not sending SNMP traps to the NMS. Which operational command should be used to verify SNMP configuration?

Accepted Answer

show snmp. The 'show snmp' command in Junos displays the current SNMP configuration, including community strings, trap destinations, and enabled trap groups. Since the issue is that the device is not sending SNMP traps, this command allows the engineer to verify that trap destinations are correctly configured and that the appropriate trap groups are enabled. Other commands like 'show system uptime' or 'show route' do not provide any SNMP-specific configuration details.

Answer

show system uptime

Answer

show route

Answer

show interfaces terse

Question 2

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 3

After a software upgrade, BGP sessions are not establishing. The engineer runs 'show bgp summary' and sees that all sessions are in Idle state. What is the most likely cause?

Accepted Answer

The BGP group configuration is missing. The Idle state in BGP indicates that the session has not started the connection process, often because the BGP configuration is incomplete or missing. If the BGP group configuration is missing, the router has no peers to initiate sessions with, so all sessions remain in Idle. This is the most likely cause when all sessions are in Idle after a software upgrade, as configuration elements may be lost or not applied.

Answer

The interface is administratively down

Answer

The router has a full BGP table

Answer

The firewall filter is blocking ICMP

Question 4

A junior engineer needs to collect a snapshot of the current system state, including routing tables, interfaces, and configuration, for a support ticket. Which command achieves this?

Accepted Answer

request support information. The 'request support information' command is the correct choice because it collects a comprehensive snapshot of the current system state, including routing tables, interface details, configuration, logs, and other operational data into a single archive file. This is specifically designed for support tickets, as it bundles all relevant diagnostic information in one step, unlike individual show commands that only capture partial data.

Answer

show configuration

Answer

show interfaces

Answer

show route

Question 5

A network engineer wants to schedule a reboot of a Juniper device at 3:00 AM. Which command should be used?

Accepted Answer

request system reboot at 03:00. The 'request system reboot at 03:00' command schedules a one-time reboot of the Juniper device at the specified time (3:00 AM). The 'at' parameter allows the engineer to set an absolute time for the reboot, which is the exact requirement for scheduling a reboot at a specific future time.

Answer

request system configuration rescue save

Answer

request system reboot

Answer

load override /config/juniper.conf.gz

Question 6

A router is experiencing intermittent packet loss. The engineer runs 'show interfaces ge-0/0/0 extensive' and notices a high number of input errors but no output errors. What is the most likely cause?

Accepted Answer

A faulty transceiver. A high number of input errors with no output errors on a Juniper interface typically indicates a Layer 1 issue at the receiving end. A faulty transceiver can cause signal degradation, leading to CRC errors, framing errors, or alignment errors, all of which are counted as input errors. Since output errors are absent, the problem is not with the router's transmission but with the incoming signal quality.

Answer

The cable is too long

Answer

MTU mismatch

Answer

The interface is oversubscribed

Question 7

An engineer needs to check the last time the configuration was changed. Which command provides this information?

Accepted Answer

show system commit. The 'show system commit' command displays the commit history, including the date, time, and user for each configuration change. This allows the engineer to see exactly when the last configuration was committed, which is the definitive way to determine the last time the configuration was changed.

Answer

show configuration | display set

Answer

show system alarms

Answer

show system uptime

Question 8

A BGP session is flapping. The engineer runs 'show log messages' and sees 'BGP recv Notification' with error code 'Cease'. What does this indicate?

Accepted Answer

The remote peer closed the connection. A BGP Cease notification indicates that the remote peer has closed the BGP session, often due to an administrative shutdown, configuration change, or error condition on the peer. The 'BGP recv Notification' message means the local router received this notification from the peer, so the remote peer initiated the closure.

Answer

The BGP table is full

Answer

The hold timer expired

Answer

The interface went down

Question 9

Which THREE statements are true about the 'show interfaces ge-0/0/0 extensive' command output?

Accepted Answer

It displays a detailed count of errors. The 'show interfaces ge-0/0/0 extensive' command provides a comprehensive view of the interface. It displays detailed error counters (e.g., CRC, frame errors), traffic statistics (e.g., bytes, packets), and the administrative status (e.g., 'Up' or 'Down'). Options A, C, and E are true statements about the output.

Answer

It includes only layer 1 information

Answer

It shows the interface configuration

Question 10

Which THREE commands are used for operational monitoring of routing protocols?

Accepted Answer

show isis adjacency. The 'show isis adjacency' command is used to verify the state of IS-IS neighbor adjacencies, which is a core operational monitoring task for the IS-IS routing protocol. It displays the interface, neighbor system ID, level, and adjacency state (e.g., Up, Down, Initializing), allowing an engineer to confirm that IS-IS neighbors are properly established.

Answer

show interfaces terse

Answer

show arp