Juniper JN0-223 Automation and DevOps Associate (JNCIA-DevOps) Exam Practice Test

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.

In Python, lists are zero-indexed, meaning the first element of the list is at index 0. The given script is:

pythona = [1, 2, 3, 4, 5, 6, 7, 8, 9]

print(a[0])

a[0]refers to the first element in the lista, which is1.

So, the output of theprint(a[0])command is1.

Option A is correct because Python indexing starts at 0, making the first element of the list at index 0.

Python Official Documentation: Covers list indexing and operations.

Python Programming Tutorials: Provide examples of list indexing.

References:

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.

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:

XML Schema Definition (XSD) files are used to define the structure and data types of an XML document. They ensure that the XML document adheres to a specific structure by defining the allowed elements, attributes, and their data types, thereby enforcing a consistent format.

Option Ais correct because XSD files define the elements, attributes, and structure (hierarchy) of an XML document.

Option Dis correct because XSD files provide a standardized format, ensuring that all parties working with the XML document use the same set of tags and structure.

Option B (Every XML document must have an XSD file defined for it)is incorrect; not every XML document requires an XSD file, although it's beneficial for validation.

Option C (An XSD file is not an XML document)is incorrect because XSD files themselves are written in XML.

Supporting References:

W3C XML Schema Definition (XSD) Documentation:Explains the purpose and structure of XSD files, including their role in defining XML document schemas.

In JSON (JavaScript Object Notation), the two primary data structures are:

Objects:These are collections of key-value pairs, where each key is a string, and the value can be a string, number, array, boolean, or another object. In Python, this structure is analogous to a dictionary.

Arrays:These are ordered lists of values, where each value can be of any data type, including another array or object. In Python, this structure is similar to a list.

Option A (tuples)andOption D (dictionaries)refer to Python-specific data structures and are not directly used in JSON.

Supporting References:

JSON Documentation and Tutorials:JSON objects and arrays are the standard data structures used in this format, as described in many tutorials and the official JSON documentation.

The NETCONF protocol, used for network management, utilizes XML for encoding the RPC (Remote Procedure Call) requests and responses. XML is chosen because of its flexibility and ability to represent hierarchical data structures, making it well-suited for representing network configurations and states.

Option Bis correct because XML is the standard format used for NETCONF RPC payloads.

Options A (YAML), C (JSON), and D (HTML)are incorrect because these formats are not used by NETCONF for its RPC payloads.

Supporting References:

RFC 6241 - NETCONF Protocol:This RFC describes the use of XML for encoding NETCONF messages.

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.

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. It supports data in CSV format:The Junos REST API supports multiple data formats for transferring information between systems, including XML, JSON, andCSV (Comma Separated Values). This flexibility allows for easier data parsing, especially in environments where structured data (likeCSV) is a standard. CSV is often used for bulk data export or import and reporting purposes, making it an essential format for automation tasks involving external systems or large datasets.

Example Usage in REST API:When using the Junos REST API, a user can request configuration or operational data and specify the response format (XML, JSON, or CSV). CSV is particularly useful when integrating Junos devices with systems that require easily readable, tabular formats.

Themgd(Management Daemon) process in Junos is responsible for handling XML automation requests. This daemon manages the configuration and operational commands received via NETCONF, which uses XML for data exchange. Themgdprocess parses the XML data and applies the necessary configuration or retrieves the requested information.

Option Bis correct becausemgdis the process that handles XML-based requests in Junos.

Options A (jsrpd), C (rpd), and D (jsd)are incorrect because they are responsible for different functions, such as routing protocols and services, not XML automation.

Supporting References:

Juniper Networks Management Daemon (mgd) Documentation:Provides an overview of the responsibilities of themgdprocess, including handling XML requests.

DevOps is a set of practices, tools, and cultural philosophies that aims to integrate and automate the processes between software development and IT operations teams. The primary goal of DevOps is to shorten the systems development life cycle and provide continuous delivery with high software quality.

Option C is correct because DevOps fundamentally focuses on breaking down the silos between development and operations teams, fostering a collaborative environment where these teams work together throughout the entire software lifecycle. This collaboration extends to other stakeholders, including quality assurance (QA), security, and more, to ensure that the product is continuously delivered and improved based on real-time feedback.

DevOps promotes a cultural shift where teams are no longer isolated but work together to share responsibilities, which leads to increased efficiency, faster problem resolution, and a more streamlined deployment process. This culture of collaboration is supported by various automation tools and practices such as Continuous Integration (CI), Continuous Deployment (CD), Infrastructure as Code (IaC), and automated testing.

Supporting References:

Juniper Networks Automation and DevOps Documentation:This documentation emphasizes the importance of collaboration between development and operations teams to streamline processes and improve efficiency, aligning perfectly with the principles of DevOps.

"The DevOps Handbook"by Gene Kim, Patrick Debois, John Willis, and Jez Humble: This book provides an in-depth look into how DevOps practices enhance collaboration and lead to faster, more reliable software delivery.

IEEE and Industry Standards:While DevOps practices are widely adopted, they are not defined or maintained by IEEE or any other formal standards body, which is why option D is incorrect.

In Junos PyEZ, theConfigobject provides various methods for interacting with device configurations. Two of the key methods are:

lock():This method locks the candidate configuration database to prevent other users or processes from making changes while you are modifying the configuration.

config():This method is used to create aConfigobject that represents the configuration database, allowing you to load, modify, and commit configuration changes.

Option C (lock)andOption D (config)are correct because they are valid methods provided by the PyEZConfigobject.

Option A (commie)andOption B (device)are incorrect as they are not methods of theConfigobject.

Supporting References:

Junos PyEZ Documentation:Details the methods available in theConfigobject, includinglock()andconfig().

Junos automation relies on several key processes to handle various automation and API interactions. Let's break down the two key processes involved:

jsd (Junos Script Daemon):The jsd process is responsible for handling automation scripts, including Python and SLAX scripts, as well as handling JET (Junos Extension Toolkit) API requests. This process is fundamental in the automation framework of Junos, as it deals with external and internal API requests, ensuring that the necessary scripts are executed when specific triggers or events occur.

kmd (Key Management Daemon):The kmd process is involved in key management for IPsec and other security services. While its primary function is related to managing cryptographic keys, it plays a role in Junos automation by enabling secure communication and ensuring that automation tasks involving security services (such as automated IPsec tunnel creation) are handled securely.

Why the Other Options Are Incorrect:

A. mod:This process doesn't exist as part of the Junos automation framework. It's likely a distractor.

C. ifd:The ifd process is associated with the physical interfaces on the device and does not play a role in automation or script processing.

References from Juniper Documentation:

Junos Automation Processes

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.