JN0-223 Practice Exam Questions with Answers Automation and DevOps Associate (JNCIA-DevOps) Certification

A commit script in Junos is used to enforce policies and configuration constraints on the device. These scripts are written in Extensible Stylesheet Language Transformations (XSLT) or Python and are executed automatically during the commit process of a configuration change.

In this context, to prevent the deletion of the SNMP configuration, a commit script is the appropriate choice. It can be designed to check the configuration changes being committed and reject any commit that attempts to delete or modify the SNMP configuration. This script essentially acts as a gatekeeper, ensuring that only allowable changes are committed to the device configuration.

Supporting References:

Juniper Networks Commit Scripts Documentation:The official Juniper documentation provides examples and use cases of commit scripts, including how they can be used to prevent unauthorized changes to the device configuration.

"Junos Automation Scripting"by Jonathan Looney: This resource gives practical examples and best practices for creating commit scripts to enforce configuration policies in Junos OS.

A. The Junos REST API client is on-box:The Junos REST API ison-box, meaning it is hosted directly on the Junos OS device. This allows you to interact with the device through RESTful API calls without needing an external client to act as an intermediary. With the on-box REST API, users can manage and automate configuration and operational tasks directly from the Junos device itself using HTTP/HTTPS protocols. This simplifies automation and remote management since the API server is embedded within the device.

Key Automation Capabilities of On-box REST API:

Supports configuration, monitoring, and operational commands.

Allows for direct device interaction via tools like curl, or through custom-built automation scripts.

XPath is a query language used for selecting nodes from an XML document. It supports various logical operators that can be used to create complex queries. The two standard logical operators supported by XPath are:

NOT:This operator negates a condition, returningtrueif the condition is false, and vice versa.

AND:This operator is used to combine two conditions, and it returnstrueonly if both conditions are true.

Option A (IOR)andOption D (MAMD)are not standard XPath operators.

Supporting References:

XPath Documentation:The W3C XPath specification lists the standard operators supported in XPath, includingANDandNOT.

When using theset rest control configurationcommand on a Junos device, you have several options to control access to the REST API. Two effective methods include:

Limiting the number of simultaneous connections:This ensures that the REST API is not overwhelmed by too many concurrent requests, which could potentially lead to performance issues or denial of service.

Limiting access to certain source IP addresses:This method restricts API access to specific IP addresses, enhancing security by ensuring that only trusted sources can interact with the REST API.

Option A (Limit management access to only SSH)is unrelated to controlling REST API access specifically.

Option B (Limit management access to specific users)might be relevant in a different context, but it is not directly tied to REST API control via the specific command mentioned.

Supporting References:

Juniper Networks REST API Documentation:This documentation explains how to configure and control access to the REST API on Junos devices, including connection limits and IP-based access control.

To configure unique IP addresses on individual machines using Junos PyEZ, you can use the following features:

YAML Data File (C): YAML files are used to store configuration data in a human-readable format. They are often used in combination with Jinja2 templates to provide the data necessary for template rendering.

Jinja2 Template (D): Jinja2 is a templating engine for Python that allows you to create dynamic templates. When used with Junos PyEZ, a Jinja2 template can be filled with data (such as IP addresses from a YAML file) to generate configuration snippets that are applied to different devices.

Options A (SCP module) and B (BSON data file)are not typically used with Junos PyEZ for this purpose.

Junos PyEZ Documentation: Discusses the use of YAML files and Jinja2 templates for generating configurations.

Jinja2 Templating Documentation: Provides details on how to create and use templates in Python scripts.

References:

In Junos, theJET (Junos Extension Toolkit)API supports direct modification of theEphemeral database. The Ephemeral database is a temporary configuration database used in Junos OS, allowing for changes that do not persist after a reboot unless explicitly committed to the permanent configuration.

JET API: Allows for high-performance interactions with Junos, including the ability to make changes to the Ephemeral database, which is useful for temporary configurations, dynamic policies, and other operational tasks.

Other options like WebSocket, SOAP, and REST do not provide direct access to the Ephemeral database in Junos.

Juniper Networks JET Documentation: Details how JET API interacts with the Ephemeral database.

Junos Automation and DevOps Documentation: Discusses the use of JET for automation and dynamic configuration.

References:

In Python, the correct syntax to prompt the user for input and store that input in a variable is:

input(prompt): Theinput()function is used to take input from the user. The string provided as an argument (inside the parentheses) is displayed as a prompt to the user. The input provided by the user is returned as a string and can be stored in a variable.

Example:

hostIP = input("Device IP address: ")

In this example,"Device IP address: "is the prompt displayed to the user, and the user's input will be stored in the variablehostIP.

Options B, C, and D are syntactically incorrect in Python.

Python Official Documentation: Describes the use of theinput()function for getting user input.

Python Tutorials: Various tutorials demonstrate how to properly use theinput()function in scripts.

References:

NETCONF (Network Configuration Protocol) is a standard protocol defined for managing network devices. NETCONF operates in a layered architecture, which includes the following key layers:

Operations Layer: This layer deals with the actual operations like , , , and others. It receives RPC (Remote Procedure Call) requests from a remote NETCONF client and processes these requests.

Messages Layer: This layer is responsible for encoding the RPCs and sending them over the network. It handles the communication between the NETCONF client and server, ensuring that the RPC messages are correctly formatted (usually in XML) and transmitted.

Statement Bis correct because the Messages layer is responsible for sending RPCs to a remote NETCONF server.

Statement Cis correct because the Operations layer is where the NETCONF server receives and processes the RPCs sent by the client.

Supporting References:

Juniper Networks NETCONF Documentation:Provides a detailed breakdown of the NETCONF protocol layers and their functions.

RFC 6241:The official specification for NETCONF, which describes the layered architecture, including the operations and messages layers.

Thejsd(Junos Script Daemon) process is responsible for handlingJET (Junos Extension Toolkit)automation requests. The JET framework allows for more programmable interactions with Junos devices, using APIs to manage and automate network functions. The jsd process handles these API requests, executes the relevant scripts, and interacts with the Junos configuration and operational states accordingly.

JET enables developers to write applications that interact with the Junos OS through APIs, providing a powerful tool for network automation, monitoring, and configuration management. The jsd process ensures that all JET-related operations are processed and executed properly.

Why the Other Options Are Incorrect:

A. jsrpd:This is not a process associated with JET automation requests.

B. mgd:The mgd process is responsible for handling management tasks like CLI commands and configuration changes but is not directly responsible for JET automation requests.

C. rpd:The rpd (Routing Protocol Daemon) manages routing protocols like BGP and OSPF but has no involvement in JET automation.

References from Juniper Documentation:

Juniper's documentation on JET and the jsd process outlines how this daemon manages script and API request processing for automation tasks.

REST API requests can be made using various tools that support HTTP methods. Two common tools are:

cURL:A command-line tool that allows you to send HTTP requests, including GET, POST, PUT, and DELETE. It is widely used for testing and interacting with RESTful APIs due to its simplicity and flexibility.

Web Browser:Modern web browsers can be used to send HTTP GET requests directly by entering the URL into the address bar. Additionally, browser extensions like Postman or built-in developer tools can be used to construct and send more complex REST API requests.

Option B (NETCOfJF)is incorrect as it does not refer to a standard tool for making REST API requests.

Option D (SSH)is incorrect because SSH is a protocol used for secure remote login and command execution, not for sending REST API requests.

Supporting References:

cURL Documentation:Official cURL documentation provides extensive information on how to use cURL to interact with REST APIs.

Web Development and REST API Guides:Many web development resources and REST API documentation recommend using web browsers and tools like cURL for testing and interacting with APIs.

NETCONF (Network Configuration Protocol) is used for network device management and can operate over SSH. The following are true about NETCONF:

Default Port 830 (B): By default, NETCONF uses port 830 for communication over SSH. This is the standard port reserved for NETCONF sessions.

Use of Default SSH Port (D): NETCONF can also operate over the standard SSH port (port 22) if configured to do so. This allows flexibility in network management scenarios where port 830 might not be available or used.

Options A and C are incorrectbecause they refer to incorrect or non-applicable port numbers for NETCONF.

IETF RFC 6241: Specifies the use of NETCONF over SSH, including port details.

Juniper Networks NETCONF Documentation: Discusses the configuration and operation of NETCONF on Junos devices, including port usage.

References: