Juniper Networks Certified Associate Junos: CLI Mode for Configuration Changes

B

The correct answer is B. configuration mode.

Explanation: Junos OS, the operating system used in Juniper Networks devices, provides three main CLI modes: operational mode, configuration mode, and shell mode.

Operational mode is the default CLI mode that displays system status and allows you to run operational commands. In operational mode, you can view system information, monitor network interfaces and protocols, and troubleshoot network issues. However, you cannot make any configuration changes in this mode.

Configuration mode is the CLI mode that allows you to make configuration changes to the device. To enter configuration mode, you must first enter operational mode and then issue the "configure" command. Once you enter configuration mode, you can use various configuration statements to configure the device according to your requirements.

For example, you can configure interfaces, routing protocols, security policies, and other network settings. Configuration mode provides a hierarchy of configuration levels, where you can configure the entire device or specific parts of the device, such as interfaces or protocols.

Enable mode is a privilege mode that allows you to access configuration mode and execute certain privileged commands. To enter enable mode, you must enter the "enable" command in operational mode and provide the correct password. Once you enter enable mode, you can access configuration mode and execute privileged commands, such as system-level configuration or software upgrades.

Active mode is not a valid CLI mode in Junos OS.

In summary, configuration mode is the CLI mode that allows you to make configuration changes to a Juniper Networks device. To enter configuration mode, you must first enter operational mode and then issue the "configure" command.