Junos Configuration Basics

A network engineer is configuring a new Juniper device. They intend to apply a firewall filter to an interface to only allow SSH traffic from a specific management subnet. Which configuration approach best follows Juniper best practices?

A junior engineer is asked to change the hostname of a Juniper device from 'Router-1' to 'Core-Router'. Which command sequence correctly commits the change?

During troubleshooting, an engineer notices that BGP sessions are flapping. They suspect that the issue might be related to the maximum number of routes allowed. To see if the BGP import policy is rejecting routes, which operational command would provide immediate insight?

When configuring a new Juniper router, an engineer needs to ensure that configuration changes are not automatically committed after a certain time if not explicitly confirmed. Which configuration parameter controls this?

A network administrator wants to view the current candidate configuration that has not yet been committed. Which command should be used?

An engineer is designing a network and needs to ensure that management traffic (SSH, SNMP) is always permitted, even if an interface firewall filter is applied. Which Juniper best practice should be followed?

A network engineer needs to add an additional IP address to an interface that already has a primary IP configured. Which method should be used?

After making several configuration changes, an engineer wants to see what changes were made in the candidate configuration compared to the last committed configuration. Which command should be used?

Which TWO statements are true regarding the Junos OS commit model?

Which THREE are valid methods to apply a firewall filter in Junos?

Which TWO are correct statements about the Junos configuration hierarchy?

Which THREE statements about the 'commit' command are correct?

Refer to the exhibit. An engineer has made changes to the candidate configuration. What will happen when the engineer issues the 'commit' command?

Refer to the exhibit. An engineer notices that SNMP traffic from source 10.1.1.1 is being rejected on interface ge-0/0/1. The engineer wants to allow SNMP from this source while still blocking other SNMP traffic from the 10.0.0.0/8 range. Which change should be made?

A company has a Juniper MX router acting as a BGP route reflector. The router has two routing instances: 'internet' and 'management'. The 'internet' instance uses a firewall filter to block traffic to the router's loopback address from external sources. After a recent configuration change, the engineer notices that SSH access to the router's loopback IP (10.0.0.1) from the internal management network (192.168.0.0/16) is being dropped. The firewall filter for the loopback interface in the 'internet' instance is correctly configured to allow traffic from 192.168.0.0/16. The management instance has no firewall filter applied. The engineer suspects that the issue is related to how the routing instances interact with the loopback interface. Which of the following is the most likely cause and solution?

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?

Which TWO statements about configuration groups in Junos are correct? (Choose two.)

Refer to the exhibit. An engineer configures interface ge-0/0/0 with both IPv4 and IPv6 addresses. The engineer notices that the interface is operationally up, but the IPv6 address is not pingable from a directly connected host. The host has an IPv6 address in the same subnet. What is the most likely cause?

Your company has deployed a Juniper MX router at a branch office. The router has two upstream connections to different ISPs. The configuration currently uses a single static default route to ISP-A. The network team wants to add redundancy so that if ISP-A fails, traffic automatically uses ISP-B. The ISP-B connection is already configured on interface ge-1/0/0 with IP address 203.0.113.2/30. The next-hop IP for ISP-B is 203.0.113.1. The routing table should have a backup default route with a higher metric. Which configuration change meets the requirement?

An engineer needs to apply a configuration change to the Junos device that must survive a reboot. Which configuration mode command should be used to save the changes?

Which TWO statements correctly describe Junos configuration hierarchy and management?

Refer to the exhibit. What is the purpose of the 'family inet6' configuration on interface ge-0/0/0?

Order the steps to configure a VLAN on an EX Series switch running Junos.

Order the steps to configure a BGP peering session in Junos.

Match each Junos configuration mode command to its purpose.

Match each Junos software process to its role.

An administrator makes changes to the candidate configuration and wants to automatically revert to the previous configuration if the changes cause a loss of connectivity. Which method should be used?

A network engineer wants to quickly restore the device to a known good configuration after a failed change. What is the recommended approach?

Which configuration group feature allows an administrator to apply common configuration settings to multiple interfaces without repeating the configuration?

An administrator wants to apply the same BGP configuration to all interfaces whose names start with 'ge-'. Which approach would dynamically match these interfaces?

Under what circumstance would the 'deactivate' command be useful in Junos configuration?

An administrator needs to change a portion of the configuration by matching a pattern and replacing it with new text. Which Junos configuration mode command should be used?

A company has two Juniper routers in a high-availability cluster with dual Routing Engines. The administrator performs a commit on the primary RE. What is the effect of using the 'commit synchronize' command?

An engineer needs to load a full configuration from a text file onto a Junos device, replacing the entire candidate configuration. Which command should be used?

While in configuration mode, an administrator wants to see the difference between the candidate configuration and the active configuration. Which command accomplishes this?

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

Which THREE statements about the commit operation are correct? (Choose three.)

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

Refer to the exhibit. If the administrator now enters the command 'delete interfaces ge-0/0/0 unit 0 family inet address 192.168.1.1/24' and then commits, what will be the result?

Refer to the exhibit. What is the most likely cause of the commit check failure?

Refer to the exhibit. An administrator wants to remove the address 10.0.0.2/24 from unit 0. Which configuration mode command achieves this without affecting other configuration?

An administrator is configuring a new Junos device and wants to ensure that configuration changes are applied only after explicit commit confirmation. Which configuration statement should be used?

A network engineer needs to configure an interface on a Juniper device to use DHCP to obtain an IP address. Which hierarchy is used to apply this configuration?

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?

A Juniper device has multiple candidate configurations loaded. The administrator wants to discard all uncommitted changes and revert to the last committed configuration. Which command should be used?

When configuring OSPF on a Juniper router, an engineer applies the 'area 0.0.0.0 interface ge-0/0/1.0 passive' command. What is the effect of this configuration?

A network administrator is configuring a GRE tunnel on a Juniper device. The tunnel source is loopback 0 and destination is 192.0.2.1. Which additional configuration is necessary on the tunnel interface for the tunnel to become operational?

An administrator is configuring a static route to a remote network 10.10.10.0/24 via next-hop 192.168.1.1. Which command correctly adds this route?

A junior engineer is tasked with configuring a firewall filter to only allow SSH access to the management interface. The management interface is fxp0. Which configuration is correct?

While troubleshooting a routing loop, an administrator captures traffic on an interface and sees packets with TTL=1 being forwarded. This indicates a potential misconfiguration. Which command can be used to verify whether the interface is configured with 'no-ttl-propagate'?

Refer to the exhibit. The administrator applied a firewall filter named BLOCK-ICMP on the inbound direction of ge-0/0/0. However, pings from the router to 10.0.0.2 are successful. Why is this?

Refer to the exhibit. A route policy named DENY-RFC1918 is configured. What is the final action of this policy for a route matching 172.20.0.0/16?

Refer to the exhibit. The administrator has configured a default static route. However, the route does not appear in the routing table. Based on the output, what is the most likely issue?

Which TWO statements about the 'commit' operation in Junos are correct?

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

Which TWO commands can be used to view the current active configuration on a Juniper device?

An engineer wants to revert all uncommitted changes in the candidate configuration and start fresh from the currently active configuration. Which command should be used?

A network administrator wants to add a new interface configuration to the candidate configuration while preserving all existing candidate changes. Which command should be used?

During a maintenance window, an engineer issues 'commit confirmed 5' but the change causes a connectivity loss. The engineer is unable to reconnect to the device before the timeout expires. What will happen?

Which operational mode command displays the differences between the candidate configuration and the active configuration?

An engineer needs to configure a static route on a Juniper device. Which statement is true regarding the configuration process?

After a series of configuration changes, an engineer wants to see only the lines that will be added or modified when the candidate is committed. Which command achieves this?

Which command saves the active configuration to a file name other than the default rescue configuration?

An engineer issues the 'rollback 3' command in configuration mode. What is the effect?

A junior administrator is told to implement configuration changes that must survive a reboot. Which statement is correct?

Which TWO statements about configuration storage in Junos are true?

Which THREE statements about commit options are true?

Which TWO statements about configuration archival in Junos are true?

Refer to the exhibit. What will happen if the engineer commits this configuration?

Refer to the exhibit. What is the effect of the pending changes?

Refer to the exhibit. What is the most likely cause of the error?

A network engineer needs to make a change to a Junos device and ensure the change can be reverted if it causes issues. Which feature should be used?

A junior administrator wants to discard all uncommitted changes made in the current configuration session. Which command accomplishes this?

An engineer needs to add a set of configuration parameters to a group that can be inherited by multiple interfaces. Which configuration element should be used?

An administrator wants to save the current configuration as a rescue configuration. Which command sequence is correct?

A technician needs to load a new configuration file that replaces only the specific hierarchy paths present in the file, leaving all other existing configuration unchanged. Which load statement is appropriate?

In a dual Routing Engine (RE) setup, an engineer commits a configuration change that should be applied to both REs synchronously. What is the correct command to ensure both REs receive the same configuration immediately?

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

An administrator wants to view the differences between the current candidate configuration and the last committed configuration. Which command displays this?

A network engineer needs to restore the factory-default configuration on a Junos device. Which command sequence is correct?

Which TWO statements are true about the 'commit' operation in Junos?

Which TWO of the following are valid methods to load a configuration file into a Junos device?

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

Scenario: Your company has a Juniper MX Series router at a branch office running Junos 18.4. The device has been in production for two years with a stable configuration. Yesterday, a senior engineer made several changes to the OSPF configuration to optimize routing for a new link. They committed the changes and left for the day. This morning, the branch office experiences intermittent connectivity, and the OSPF neighbor relationships are flapping. You suspect the recent OSPF changes caused the issue. You have remote console access to the router. The goal is to restore network stability as quickly as possible while preserving the ability to re-apply the changes after troubleshooting. Which course of action should you take?

Scenario: Your company has a Juniper SRX300 firewall used as a branch gateway. It runs Junos 15.1X49. The firewall has multiple security policies, NAT rules, and VPN tunnels. Recently, you added a new security policy to allow traffic from the internal network to a specific public server. After committing, you notice that the firewall is logging repeated denials for traffic that should be matched by the new policy. The policy appears correctly configured in the candidate configuration. You want to verify that the policy is actually active and check for any hidden rules that might be causing the issue. Which of the following is the most effective first step to troubleshoot this problem?

An engineer has modified the configuration and wants to apply changes but also wants to verify that the changes are syntactically correct before committing. What command should the engineer use?

A network administrator wants to configure a user account for a junior engineer. The junior engineer should only be able to view configuration and use operational commands, but not modify anything. Additionally, the junior engineer should be required to authenticate using a local password. Which configuration accomplishes this?

Which TWO statements are true about the Junos configuration hierarchy?

Which THREE of the following are valid commit options in Junos?

You are a junior network engineer tasked with configuring a Juniper device for the first time. The device has just been powered on and you have console access. The device boots normally and shows the login prompt. There is no root password configured, but when you try to log in as root, you are prompted for a password. You do not have any previous configuration access. What should you do to gain access and begin configuring the device?

A network operations team has received a new Juniper router to replace an existing legacy router. The team needs to apply a baseline configuration that includes system settings, interfaces, and security policies. The configuration is provided as a text file containing Junos configuration hierarchy syntax (e.g., 'system { host-name... }'). The engineer connects to the console and sees the prompt 'root@%'. What is the most efficient way to apply the configuration?

A network engineer accidentally committed a configuration on a Juniper router that caused a loss of management access via SSH and SNMP. The engineer has console access and the device is still operational. Before the change, the engineer had saved a rescue configuration using 'request system configuration rescue save'. Which action should the engineer take to restore management access most quickly?

A company runs a Juniper SRX firewall cluster consisting of two nodes (node0 primary, node1 secondary). The cluster has been stable. During maintenance, you modify the configuration on node0 and commit. After the commit, the cluster status shows node1 as 'ineligible'. You suspect a configuration mismatch. What should you do to synchronize the configuration without disrupting traffic?

A Juniper router experiences a power outage. After power is restored, the router fails to boot completely and stops at the loader (U-Boot) prompt. You have console access. Before the outage, you had saved a rescue configuration. How can you load the rescue configuration to recover the system?