Practice Free JN0-224 Exam Online Questions
Question #1
You want to perform a dry run on the myPlays playbook and use a custom inventory file called myRouters.ini.
Which Ansible command would you use in this scenario?
- A . ansible-playbook myPlays –check -i myRouters.ini
- B . ansible-playbook myPlays ―extra-vars "inventory_file=myRouters .ini"
- C . ansible-playbook myPlays ―extra-vars "dry run=True" myRouters.ini
- D . ansible-playbook myPlays ―limit myRouters
Correct Answer: B
Question #2
YAML uses which two data structures? (Choose two.)
- A . arrays
- B . mappings
- C . sequences
- D . objects
Correct Answer: B, C
B, C
Explanation:
YAML (YAML Ain’t Markup Language) primarily uses two data structures:
Mappings: These are key-value pairs, similar to dictionaries or hashes in programming languages. In YAML, mappings are used to represent associative arrays or objects. They are defined with a colon (:) separating the key from the value.
Example:
key: value
name: John Doe
Sequences: These are ordered lists of items, equivalent to arrays or lists in other programming languages. Sequences in YAML are denoted by a dash (-) followed by a space and then the item.
Example:
fruits:
– Apple
– Banana
– Cherry
Detailed Explanation
Mappings (B) allow you to define relationships between keys and values, making it possible to represent more complex data structures like dictionaries or objects.
Sequences (C) allow you to represent ordered collections, which is important for listing elements that must maintain a specific order.
YAML is often used in configuration files and data serialization in DevOps environments, such as in Ansible playbooks, Kubernetes manifest files, and CI/CD pipeline definitions. Its simplicity and human-readable format make it a popular choice for these applications.
Reference: YAML Official Documentation: YAML’s specification outlines these core data structures.
Juniper Automation and DevOps Documentation: Provides best practices for using YAML in network automation scripts and configuration management.
B, C
Explanation:
YAML (YAML Ain’t Markup Language) primarily uses two data structures:
Mappings: These are key-value pairs, similar to dictionaries or hashes in programming languages. In YAML, mappings are used to represent associative arrays or objects. They are defined with a colon (:) separating the key from the value.
Example:
key: value
name: John Doe
Sequences: These are ordered lists of items, equivalent to arrays or lists in other programming languages. Sequences in YAML are denoted by a dash (-) followed by a space and then the item.
Example:
fruits:
– Apple
– Banana
– Cherry
Detailed Explanation
Mappings (B) allow you to define relationships between keys and values, making it possible to represent more complex data structures like dictionaries or objects.
Sequences (C) allow you to represent ordered collections, which is important for listing elements that must maintain a specific order.
YAML is often used in configuration files and data serialization in DevOps environments, such as in Ansible playbooks, Kubernetes manifest files, and CI/CD pipeline definitions. Its simplicity and human-readable format make it a popular choice for these applications.
Reference: YAML Official Documentation: YAML’s specification outlines these core data structures.
Juniper Automation and DevOps Documentation: Provides best practices for using YAML in network automation scripts and configuration management.
Question #3
Which two statements are correct about using the Junos REST API? (Choose two.)
- A . It supports data In CSV format.
- B . It must use SSH for a connection.
- C . NETCONF is not supported.
- D . It is a simple configuration.
Correct Answer: A, D
A, D
Explanation:
A, D
Explanation:
Question #4
Which Junos configuration database is updated by PyEZ by default?
- A . shared
- B . dynamic
- C . private
- D . ephemeral
Correct Answer: C
C
Explanation:
An event script is used to automate responses to system events in Junos, such as an interface going down. These scripts are triggered automatically when a specified event occurs, making them suitable for tasks like monitoring interface status and executing actions when the status changes.
Option B (event) is correct because event scripts are designed for reacting to system events like an interface going down.
Option A (commit) is used for configuration changes, Option C (operation) is used for operational tasks, and Option D (SNMP) is not applicable in this context.
Supporting
Reference: Juniper Networks Event Scripts Documentation: Details how event scripts are used to automate responses to specific system events in Junos
C
Explanation:
An event script is used to automate responses to system events in Junos, such as an interface going down. These scripts are triggered automatically when a specified event occurs, making them suitable for tasks like monitoring interface status and executing actions when the status changes.
Option B (event) is correct because event scripts are designed for reacting to system events like an interface going down.
Option A (commit) is used for configuration changes, Option C (operation) is used for operational tasks, and Option D (SNMP) is not applicable in this context.
Supporting
Reference: Juniper Networks Event Scripts Documentation: Details how event scripts are used to automate responses to specific system events in Junos
Question #5
Which data construct is used to guarantee that element names and data values remain unique in an XML document?
- A . element
- B . schema definition
- C . namespace
- D . dictionary
Correct Answer: C
C
Explanation:
In XML documents, a namespace is the data construct used to ensure that element names and data values remain unique. Namespaces prevent naming conflicts by differentiating between elements or attributes that may have the same name but different meanings. This is particularly important in XML, where documents often incorporate elements from multiple sources.
Detailed Explanation
XML Namespaces: A namespace is a collection of names, identified by a URI reference, which is used to distinguish between elements that may have identical names but different definitions or origins. This helps avoid ambiguity in the document.
How Namespaces Work: When a namespace is applied, each element or attribute in the XML document is associated with a prefix. This prefix, combined with the namespace URI, ensures that the element or attribute is uniquely identified, even if another element or attribute in the same document has the same local name but a different namespace.
Schema Definition vs. Namespace: Although an XML schema definition (XSD) can define the structure and type constraints of an XML document, it does not guarantee uniqueness of element names across different XML documents. That role is fulfilled by namespaces.
Practical Example:
xml
Copy code
<root xmlns:ns1="http://www.example.com/ns1"
xmlns:ns2="http://www.example.com/ns2">
<ns1:item>Item in namespace 1</ns1:item>
<ns2:item>Item in namespace 2</ns2:item>
</root>
In this example, the item elements are in different namespaces (ns1 and ns2), which keeps them unique even though they have the same name.
Reference: Juniper Automation and DevOps Documentation: These practices highlight the importance of namespaces in XML documents to maintain the integrity and uniqueness of data, which is essential in automation scripts and configuration files.
W3C XML Namespace Specification: The World Wide Web Consortium (W3C) standard for XML Namespaces defines how namespaces should be used to avoid name conflicts.
Namespaces are a crucial concept in XML, ensuring that data can be consistently managed and
interpreted correctly, particularly in complex systems where multiple XML documents or schemas are involved.
C
Explanation:
In XML documents, a namespace is the data construct used to ensure that element names and data values remain unique. Namespaces prevent naming conflicts by differentiating between elements or attributes that may have the same name but different meanings. This is particularly important in XML, where documents often incorporate elements from multiple sources.
Detailed Explanation
XML Namespaces: A namespace is a collection of names, identified by a URI reference, which is used to distinguish between elements that may have identical names but different definitions or origins. This helps avoid ambiguity in the document.
How Namespaces Work: When a namespace is applied, each element or attribute in the XML document is associated with a prefix. This prefix, combined with the namespace URI, ensures that the element or attribute is uniquely identified, even if another element or attribute in the same document has the same local name but a different namespace.
Schema Definition vs. Namespace: Although an XML schema definition (XSD) can define the structure and type constraints of an XML document, it does not guarantee uniqueness of element names across different XML documents. That role is fulfilled by namespaces.
Practical Example:
xml
Copy code
<root xmlns:ns1="http://www.example.com/ns1"
xmlns:ns2="http://www.example.com/ns2">
<ns1:item>Item in namespace 1</ns1:item>
<ns2:item>Item in namespace 2</ns2:item>
</root>
In this example, the item elements are in different namespaces (ns1 and ns2), which keeps them unique even though they have the same name.
Reference: Juniper Automation and DevOps Documentation: These practices highlight the importance of namespaces in XML documents to maintain the integrity and uniqueness of data, which is essential in automation scripts and configuration files.
W3C XML Namespace Specification: The World Wide Web Consortium (W3C) standard for XML Namespaces defines how namespaces should be used to avoid name conflicts.
Namespaces are a crucial concept in XML, ensuring that data can be consistently managed and
interpreted correctly, particularly in complex systems where multiple XML documents or schemas are involved.
Question #6
Which statement is correct about DevOps?
- A . DevOps is a collection of strict guidelines that promotes the project completion over all other aspects.
- B . DevOps is meant to define and restrict the development and operations tools used for a project.
- C . DevOps is meant to unite the development, operations, and other teams to improve project collaborations.
- D . DevOps is a defined standard written and maintained by the IEEE standards group.
Correct Answer: C
C
Explanation:
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
Reference: 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.
C
Explanation:
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
Reference: 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.
Question #7
You are asked to use the REST API to retrieve interface configuration information from your Junos device. You decide to use a cURL HTTP GET command to retrieve this information.
In this scenario, which two statements are correct? (Choose two.)
- A . You can retrieve this data in HTML or JSON formats.
- B . You must have SSH enabled on the Junos device.
- C . You can retrieve this data in XML or JSON formats.
- D . You must Include the authentication Information with each request.
Correct Answer: C, D
C, D
Explanation:
When using the REST API to retrieve interface configuration information from a Junos device:
Data Formats (C): The information can be retrieved in XML or JSON formats. These are the two standard data formats supported by the Junos REST API for representing configuration and operational data.
Authentication (D): For each HTTP request, especially when using tools like cURL, authentication information must be included. This is typically done using basic authentication (username and password) or an authentication token.
Option A is incorrect because HTML is not a supported format for REST API data retrieval in Junos, and Option B is incorrect because SSH is not required for REST API requests; the REST API typically uses HTTP/HTTPS.
Reference: Junos REST API Documentation: Details the data formats (XML, JSON) supported by the Junos REST
API and the need for authentication.
cURL Usage with REST API: Provides examples of how to use cURL with Junos REST API, including the necessity of providing authentication.
C, D
Explanation:
When using the REST API to retrieve interface configuration information from a Junos device:
Data Formats (C): The information can be retrieved in XML or JSON formats. These are the two standard data formats supported by the Junos REST API for representing configuration and operational data.
Authentication (D): For each HTTP request, especially when using tools like cURL, authentication information must be included. This is typically done using basic authentication (username and password) or an authentication token.
Option A is incorrect because HTML is not a supported format for REST API data retrieval in Junos, and Option B is incorrect because SSH is not required for REST API requests; the REST API typically uses HTTP/HTTPS.
Reference: Junos REST API Documentation: Details the data formats (XML, JSON) supported by the Junos REST
API and the need for authentication.
cURL Usage with REST API: Provides examples of how to use cURL with Junos REST API, including the necessity of providing authentication.
Question #8
What will determine which data serialization format is used for interfacing with a system?
- A . the system’s API
- B . the operating system
- C . programming language version
- D . IDE specifications
Correct Answer: A
Question #9
Junos supports which two APIs for on-box scripting? (Choose two.)
- A . JET
- B . Puppet
- C . XML
- D . Chef
Correct Answer: A, C
A, C
Explanation:
Juniper Networks’ Junos operating system supports several APIs for on-box scripting, two of which are:
JET (Juniper Extension Toolkit): JET is a modern API framework that provides a programmable interface for interacting with Junos. It allows developers to create custom applications that run directly on Junos devices, enabling the automation of network operations. JET provides both a gRPC and a REST API interface, allowing for flexible integration with external systems.
XML API: The Junos XML API allows direct interaction with the Junos OS through XML-based requests. This API can be used to retrieve information, configure devices, and execute commands on Junos devices. The XML API is crucial for automation tasks as it provides a structured and consistent way to interact with the device’s configuration and operational data.
Detailed Explanation
JET (A) provides high-performance access to Junos routing, switching, and service elements via programmable interfaces. It is highly used for creating custom applications that require tight integration with the Junos OS.
XML (C), on the other hand, is a well-established method for interacting with Junos, especially for legacy systems or when working within environments where XML is the standard data format.
Other options like Puppet (B) and Chef (D) are not APIs provided by Junos for on-box scripting but are configuration management tools used externally to manage Junos devices.
Reference: Juniper Networks JET Documentation: Provides details on how to leverage JET APIs for automation.
Junos XML Management Protocol Guide: Describes how to use XML for scripting and automating tasks in Junos.
These APIs are key components of Juniper’s automation strategy, allowing for scalable, flexible, and efficient network operations.
A, C
Explanation:
Juniper Networks’ Junos operating system supports several APIs for on-box scripting, two of which are:
JET (Juniper Extension Toolkit): JET is a modern API framework that provides a programmable interface for interacting with Junos. It allows developers to create custom applications that run directly on Junos devices, enabling the automation of network operations. JET provides both a gRPC and a REST API interface, allowing for flexible integration with external systems.
XML API: The Junos XML API allows direct interaction with the Junos OS through XML-based requests. This API can be used to retrieve information, configure devices, and execute commands on Junos devices. The XML API is crucial for automation tasks as it provides a structured and consistent way to interact with the device’s configuration and operational data.
Detailed Explanation
JET (A) provides high-performance access to Junos routing, switching, and service elements via programmable interfaces. It is highly used for creating custom applications that require tight integration with the Junos OS.
XML (C), on the other hand, is a well-established method for interacting with Junos, especially for legacy systems or when working within environments where XML is the standard data format.
Other options like Puppet (B) and Chef (D) are not APIs provided by Junos for on-box scripting but are configuration management tools used externally to manage Junos devices.
Reference: Juniper Networks JET Documentation: Provides details on how to leverage JET APIs for automation.
Junos XML Management Protocol Guide: Describes how to use XML for scripting and automating tasks in Junos.
These APIs are key components of Juniper’s automation strategy, allowing for scalable, flexible, and efficient network operations.
Question #10
Which two statements about Ansible are correct? (Choose two.)
- A . Ansible can use a single playbook to configure devices from multiple vendors.
- B . Ansible modules must be written in Go.
- C . Ansible is an open source project.
- D . Ansible requires a license to unlock full functionality.
Correct Answer: A, C
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