Question #1
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 #2
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 #3
You are asked to develop an on-box Junos script that prevents deletion of the SNMP configuration.
Which type of script serves this purpose?
- A . commit script
- B . event script
- C . op script
- D . SNMP script
Correct Answer: A
A
Explanation:
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
Reference: 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
Explanation:
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
Reference: 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.
Question #4
A REST API client uses which two HTTP methods to execute RPC requests on the server? (Choose two.)
- A . POST
- B . HEAD
- C . GET
- D . CONNECT
Correct Answer: A, C
A, C
Explanation:
REST APIs use HTTP methods to perform different operations on resources. In the context of RPC (Remote Procedure Call) requests:
GET: This method is used to retrieve data from the server. In a REST API, it is commonly used to fetch information about resources, such as the current configuration or operational state.
POST: This method is used to send data to the server to create or update a resource. In the context of RPC, POST is often used to execute a procedure on the server that may result in the modification of a resource or triggering of an action.
Options B (HEAD) and D (CONNECT) are not typically used for executing RPC requests:
HEAD is similar to GET but only retrieves the headers, not the body of the response.
CONNECT is used to establish a tunnel to the server, primarily for SSL-encrypted communication, and is not commonly associated with RESTful RPC operations.
Supporting
Reference: Juniper Networks REST API Documentation: The documentation provides detailed information about the use of HTTP methods in Juniper’s RESTful services.
"RESTful Web Services" by Leonard Richardson and Sam Ruby: This book explains the principles of REST and how different HTTP methods, particularly GET and POST, are used to interact with RESTful APIs.
A, C
Explanation:
REST APIs use HTTP methods to perform different operations on resources. In the context of RPC (Remote Procedure Call) requests:
GET: This method is used to retrieve data from the server. In a REST API, it is commonly used to fetch information about resources, such as the current configuration or operational state.
POST: This method is used to send data to the server to create or update a resource. In the context of RPC, POST is often used to execute a procedure on the server that may result in the modification of a resource or triggering of an action.
Options B (HEAD) and D (CONNECT) are not typically used for executing RPC requests:
HEAD is similar to GET but only retrieves the headers, not the body of the response.
CONNECT is used to establish a tunnel to the server, primarily for SSL-encrypted communication, and is not commonly associated with RESTful RPC operations.
Supporting
Reference: Juniper Networks REST API Documentation: The documentation provides detailed information about the use of HTTP methods in Juniper’s RESTful services.
"RESTful Web Services" by Leonard Richardson and Sam Ruby: This book explains the principles of REST and how different HTTP methods, particularly GET and POST, are used to interact with RESTful APIs.
Question #5
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 #6
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 #7
Which two statements about NETCONF layers are correct? (Choose two.)
- A . NETCONF layers use the messages layer to receive RPCs from a remote NETCONF server.
- B . NETCONF layers use the messages layer to send RPCs to a remote NETCONF server.
- C . NETCONF layers use the operations layer to receive RPCs from a remote NETCONF server.
- D . NETCONF layers use the operations layer to send RPCs to a remote NETCONF server.
Correct Answer: B, C
B, C
Explanation:
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 <get-config>, <edit-config>, <copy-config>, 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 B is correct because the Messages layer is responsible for sending RPCs to a remote NETCONF server.
Statement C is correct because the Operations layer is where the NETCONF server receives and processes the RPCs sent by the client.
Supporting
Reference: 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.
B, C
Explanation:
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 <get-config>, <edit-config>, <copy-config>, 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 B is correct because the Messages layer is responsible for sending RPCs to a remote NETCONF server.
Statement C is correct because the Operations layer is where the NETCONF server receives and processes the RPCs sent by the client.
Supporting
Reference: 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.
Question #8
Which two tools would you use to make REST API requests? (Choose two.)
- A . cURL
- B . NETCOfJF
- C . Web browser
- D . SSH
Correct Answer: AC
AC
Explanation:
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
Reference: 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.
AC
Explanation:
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
Reference: 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.
Question #9
Which DevOps "Three way" principle addresses technical debt?
- A . feedback
- B . flow
- C . continuous experimentation and learning
- D . continuous experimentation
Correct Answer: A
A
Explanation:
In the context of the DevOps "Three Ways" principles, the feedback principle directly addresses the management of technical debt.
The "Three Ways" are core principles guiding DevOps practices, and they are as follows:
Flow: Refers to the smooth and fast flow of work through the system, from development to operations.
Feedback: Emphasizes creating effective, fast, and continuous feedback loops between teams to catch issues early, address technical debt, and ensure quality.
Continuous experimentation and learning: Encourages constant experimentation, innovation, and learning from failures to improve systems and processes over time.
Feedback and Technical Debt:
Feedback loops play a crucial role in addressing technical debt. Technical debt refers to the implied cost of additional work that arises when code or system design decisions are made for short-term gains, such as quick fixes or temporary patches. Over time, technical debt can accumulate and degrade system performance, reliability, and maintainability.
The feedback loop ensures that issues related to technical debt (such as poor code quality, design shortcuts, or performance bottlenecks) are caught early in the process, ideally before they become major problems. Continuous monitoring, testing, and reviewing help identify and resolve technical debt incrementally rather than letting it accumulate unchecked.
Automation in feedback loops: In DevOps, automated testing, continuous integration (CI), and monitoring tools provide immediate feedback to developers, highlighting areas where technical debt is increasing. This feedback is crucial for making proactive decisions about refactoring code or improving infrastructure without waiting for problems to manifest in production.
For instance, the feedback loop might expose slowdowns in application performance after each new feature is added. This would trigger a review to either refactor the feature code or improve system resources, preventing further technical debt accumulation.
Flow and Technical Debt:
While flow focuses on the smooth transition of work through the pipeline, it indirectly helps with technical debt by ensuring continuous and streamlined processes. However, feedback mechanisms are the primary tools for identifying and resolving technical debt.
Continuous Experimentation and Learning:
This principle promotes innovation and learning from failures but does not directly address technical
debt. The focus here is more on risk-taking and improvement rather than managing or eliminating technical debt.
Reference from DevOps Practices:
The Phoenix Project, a book often referenced in DevOps, discusses how feedback loops are essential for maintaining system integrity and managing technical debt effectively. By improving feedback mechanisms, teams can address small issues before they become costly to fix.
The DevOps Handbook also highlights the importance of feedback in managing technical debt, emphasizing that fast feedback allows for continuous improvement and avoids the accumulation of bad practices that would otherwise lead to technical debt.
Juniper Automation and DevOps Context: Juniper’s automation frameworks integrate feedback mechanisms using tools like continuous monitoring and automated testing. These tools help engineers track the health of network systems, identify configuration drifts, and resolve issues before they lead to significant technical debt.
Additional Resources:
The Phoenix Project by Gene Kim
The DevOps Handbook
A
Explanation:
In the context of the DevOps "Three Ways" principles, the feedback principle directly addresses the management of technical debt.
The "Three Ways" are core principles guiding DevOps practices, and they are as follows:
Flow: Refers to the smooth and fast flow of work through the system, from development to operations.
Feedback: Emphasizes creating effective, fast, and continuous feedback loops between teams to catch issues early, address technical debt, and ensure quality.
Continuous experimentation and learning: Encourages constant experimentation, innovation, and learning from failures to improve systems and processes over time.
Feedback and Technical Debt:
Feedback loops play a crucial role in addressing technical debt. Technical debt refers to the implied cost of additional work that arises when code or system design decisions are made for short-term gains, such as quick fixes or temporary patches. Over time, technical debt can accumulate and degrade system performance, reliability, and maintainability.
The feedback loop ensures that issues related to technical debt (such as poor code quality, design shortcuts, or performance bottlenecks) are caught early in the process, ideally before they become major problems. Continuous monitoring, testing, and reviewing help identify and resolve technical debt incrementally rather than letting it accumulate unchecked.
Automation in feedback loops: In DevOps, automated testing, continuous integration (CI), and monitoring tools provide immediate feedback to developers, highlighting areas where technical debt is increasing. This feedback is crucial for making proactive decisions about refactoring code or improving infrastructure without waiting for problems to manifest in production.
For instance, the feedback loop might expose slowdowns in application performance after each new feature is added. This would trigger a review to either refactor the feature code or improve system resources, preventing further technical debt accumulation.
Flow and Technical Debt:
While flow focuses on the smooth transition of work through the pipeline, it indirectly helps with technical debt by ensuring continuous and streamlined processes. However, feedback mechanisms are the primary tools for identifying and resolving technical debt.
Continuous Experimentation and Learning:
This principle promotes innovation and learning from failures but does not directly address technical
debt. The focus here is more on risk-taking and improvement rather than managing or eliminating technical debt.
Reference from DevOps Practices:
The Phoenix Project, a book often referenced in DevOps, discusses how feedback loops are essential for maintaining system integrity and managing technical debt effectively. By improving feedback mechanisms, teams can address small issues before they become costly to fix.
The DevOps Handbook also highlights the importance of feedback in managing technical debt, emphasizing that fast feedback allows for continuous improvement and avoids the accumulation of bad practices that would otherwise lead to technical debt.
Juniper Automation and DevOps Context: Juniper’s automation frameworks integrate feedback mechanisms using tools like continuous monitoring and automated testing. These tools help engineers track the health of network systems, identify configuration drifts, and resolve issues before they lead to significant technical debt.
Additional Resources:
The Phoenix Project by Gene Kim
The DevOps Handbook
Question #10
Which two processes are used by Junos automation? (Choose two.)
- A . mod
- B . jsd
- C . ifd
- D . kmd
Correct Answer: BD
BD
Explanation:
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:
BD
Explanation:
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:
Question #11
Which two statements are valid regarding Junos automation? (Choose two.)
- A . The jsd process handles XML API calls.
- B . The mgd process handles JET API requests.
- C . The jsd process handles JET API requests.
- D . The mod process handles XML API calls.
Correct Answer: C, A
C, A
Explanation:
In Junos automation, several processes handle API requests, and understanding which process handles what is crucial:
jsd Process:
XML API Calls (A): The jsd process is responsible for handling XML API calls, which are a significant part of Junos automation. XML API allows for structured and standardized communication with Junos devices, enabling automation scripts to query and configure devices.
JET API Requests (C): The jsd process also handles JET (Junos Extension Toolkit) API requests. JET provides a more modern, programmable interface for interacting with Junos OS, and jsd is the process that manages these interactions.
mgd Process (Incorrect Option):
Not for JET API Requests: The mgd process handles general management operations, such as CLI commands and managing the configuration database, but it does not handle JET API requests. That role is fulfilled by jsd.
mod Process (Incorrect Option):
Not for XML API Calls: The mod process deals with managing chassis components and is not involved in handling XML API calls.
Reference: Juniper Networks JET and XML API Documentation: Describes the roles of jsd in handling both XML and JET API requests.
Junos Automation and DevOps Documentation: Provides insights into how different processes interact with Junos APIs.
C, A
Explanation:
In Junos automation, several processes handle API requests, and understanding which process handles what is crucial:
jsd Process:
XML API Calls (A): The jsd process is responsible for handling XML API calls, which are a significant part of Junos automation. XML API allows for structured and standardized communication with Junos devices, enabling automation scripts to query and configure devices.
JET API Requests (C): The jsd process also handles JET (Junos Extension Toolkit) API requests. JET provides a more modern, programmable interface for interacting with Junos OS, and jsd is the process that manages these interactions.
mgd Process (Incorrect Option):
Not for JET API Requests: The mgd process handles general management operations, such as CLI commands and managing the configuration database, but it does not handle JET API requests. That role is fulfilled by jsd.
mod Process (Incorrect Option):
Not for XML API Calls: The mod process deals with managing chassis components and is not involved in handling XML API calls.
Reference: Juniper Networks JET and XML API Documentation: Describes the roles of jsd in handling both XML and JET API requests.
Junos Automation and DevOps Documentation: Provides insights into how different processes interact with Junos APIs.
Question #12
What is the difference between a list and a tuple in Python?
- A . Lists are immutable objects that use square brackets, and tuples are mutable objects that use parentheses.
- B . Lists are mutable objects that use square brackets, and tuples are immutable objects that use parentheses.
- C . Lists are immutable objects that use parentheses, and tuples are immutable objects that use square brackets.
- D . Lists are mutable objects that use parentheses, and tuples are immutable objects that use square brackets.
Correct Answer: B
B
Explanation:
In Python, the distinction between lists and tuples is essential for efficient programming:
Lists:
Mutable (B): This means that once a list is created, its elements can be changed, added, or removed.
Lists are versatile and commonly used when the data is expected to change.
Square Brackets: Lists are defined using square brackets [].
Example:
my_list = [1, 2, 3]
my_list[0] = 10 # Modifying the first element
Tuples:
Immutable (B): Once a tuple is created, it cannot be altered. Tuples are used when a fixed collection of items is needed, providing more integrity to the data.
Parentheses: Tuples are defined using parentheses ().
Example:
my_tuple = (1, 2, 3)
# my_tuple[0] = 10 # This would raise an error because tuples are immutable
Reference: Python Official Documentation: The Python Language Reference provides detailed information on data types like lists and tuples, including their mutability and syntax.
Automation Scripts: In the context of automation, understanding when to use mutable or immutable data structures can significantly impact script performance and reliability.
B
Explanation:
In Python, the distinction between lists and tuples is essential for efficient programming:
Lists:
Mutable (B): This means that once a list is created, its elements can be changed, added, or removed.
Lists are versatile and commonly used when the data is expected to change.
Square Brackets: Lists are defined using square brackets [].
Example:
my_list = [1, 2, 3]
my_list[0] = 10 # Modifying the first element
Tuples:
Immutable (B): Once a tuple is created, it cannot be altered. Tuples are used when a fixed collection of items is needed, providing more integrity to the data.
Parentheses: Tuples are defined using parentheses ().
Example:
my_tuple = (1, 2, 3)
# my_tuple[0] = 10 # This would raise an error because tuples are immutable
Reference: Python Official Documentation: The Python Language Reference provides detailed information on data types like lists and tuples, including their mutability and syntax.
Automation Scripts: In the context of automation, understanding when to use mutable or immutable data structures can significantly impact script performance and reliability.
Question #13
You want to use a Python package or module.
In this scenario, which statement would accomplish this task?
- A . reap
- B . dir
- C . input
- D . Import
Correct Answer: D
D
Explanation:
In Python, to use a package or module, you use the import statement. This statement allows you to load a module into your script so that you can use its functions, classes, and variables. For example, if you wanted to use the math module, you would write import math. This makes all the functions and constants in the math module available for use in your program.
Option A (reap), B (dir), and C (input) do not serve the purpose of importing modules. dir is used to list the attributes of an object, input is used to get user input, and reap is not a valid Python command related to importing modules.
Supporting
Reference: Python Documentation on Imports: The Python documentation provides clear guidelines on how to use the import statement to include modules in your Python scripts.
D
Explanation:
In Python, to use a package or module, you use the import statement. This statement allows you to load a module into your script so that you can use its functions, classes, and variables. For example, if you wanted to use the math module, you would write import math. This makes all the functions and constants in the math module available for use in your program.
Option A (reap), B (dir), and C (input) do not serve the purpose of importing modules. dir is used to list the attributes of an object, input is used to get user input, and reap is not a valid Python command related to importing modules.
Supporting
Reference: Python Documentation on Imports: The Python documentation provides clear guidelines on how to use the import statement to include modules in your Python scripts.
Question #14
Using the set rest control configuration command, what are two ways to control access to the REST API running on a Junos device? (Choose two.)
- A . Limit management access to only SSH
- B . Limit management access to specific users.
- C . Limit the number of simultaneous connections.
- D . Limit access to only certain source IP addresses
Correct Answer: C, D
C, D
Explanation:
When using the set rest control configuration command 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
Reference: 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.
C, D
Explanation:
When using the set rest control configuration command 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
Reference: 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.
Question #15
Which two statements about Junos automation are correct? (Choose two.)
- A . The Junos REST API client is on-box.
- B . Junos automation does not allow for device provisioning throuqh the console port.
- C . Junos automation allows for device provisioning through the console port.
- D . The Junos REST API client is off-box.
Correct Answer: AC
AC
Explanation:
AC
Explanation:
Question #16
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 #17
What is the correct Python script syntax to prompt for input?
- A . hostIP = input("Device IP address: ")
- B . hostIP = input{Device IP address: }
- C . hostIP = input"Device IP address: "
- D . input("Device IP address: ") = hostIP
Correct Answer: A
A
Explanation:
In Python, the correct syntax to prompt the user for input and store that input in a variable is:
input(prompt): The input() 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 variable hostIP.
Options B, C, and D are syntactically incorrect in Python.
Reference: Python Official Documentation: Describes the use of the input() function for getting user input.
Python Tutorials: Various tutorials demonstrate how to properly use the input() function in scripts.
A
Explanation:
In Python, the correct syntax to prompt the user for input and store that input in a variable is:
input(prompt): The input() 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 variable hostIP.
Options B, C, and D are syntactically incorrect in Python.
Reference: Python Official Documentation: Describes the use of the input() function for getting user input.
Python Tutorials: Various tutorials demonstrate how to properly use the input() function in scripts.
Question #18
Given the following Python script:
a = [1,2,3,4,5,6,7,8,9]
print(a[0])
What is the output of this print command?
- A . 1
- B . 2
- C . 7
- D . 9
Correct Answer: A
A
Explanation:
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 list a, which is 1.
So, the output of the print(a[0]) command is 1.
Option A is correct because Python indexing starts at 0, making the first element of the list at index 0.
Reference: Python Official Documentation: Covers list indexing and operations.
Python Programming Tutorials: Provide examples of list indexing.
A
Explanation:
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 list a, which is 1.
So, the output of the print(a[0]) command is 1.
Option A is correct because Python indexing starts at 0, making the first element of the list at index 0.
Reference: Python Official Documentation: Covers list indexing and operations.
Python Programming Tutorials: Provide examples of list indexing.
Question #19
Which Junos API supports direct modification of the Ephemeral database?
- A . JET
- B . WebSocket
- C . SOAP
- D . REST
Correct Answer: A
A
Explanation:
In Junos, the JET (Junos Extension Toolkit) API supports direct modification of the Ephemeral 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.
Reference: 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.
A
Explanation:
In Junos, the JET (Junos Extension Toolkit) API supports direct modification of the Ephemeral 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.
Reference: 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.
Question #20
Which two statements about the REST API are correct? (Choose two.)
- A . The TCP session state is maintained by the server.
- B . The REST API application is stateless.
- C . The TCP session state is maintained by the client
- D . The REST API application is stateful.
Correct Answer: B, C
B, C
Explanation:
REST (Representational State Transfer) is an architectural style for designing networked applications, and its key principles include:
Statelessness (B): Each request from the client to the server must contain all the information needed to understand and process the request. The server does not store any session state between requests, meaning each request is independent and does not rely on previous ones.
TCP Session State (C): While REST itself is stateless, the underlying TCP connection’s state, such as keeping the connection alive or managing retries, is handled by the client. The server does not retain information about the TCP connection beyond the processing of the individual request.
Options A and D are incorrect because they imply that the REST API is stateful, which contradicts the stateless nature of REST.
Reference: REST API Design Principles: Describes the stateless nature of REST and the responsibility of clients in managing session state.
Web Development Documentation: Discusses how REST APIs operate, focusing on statelessness and client-server interaction.
B, C
Explanation:
REST (Representational State Transfer) is an architectural style for designing networked applications, and its key principles include:
Statelessness (B): Each request from the client to the server must contain all the information needed to understand and process the request. The server does not store any session state between requests, meaning each request is independent and does not rely on previous ones.
TCP Session State (C): While REST itself is stateless, the underlying TCP connection’s state, such as keeping the connection alive or managing retries, is handled by the client. The server does not retain information about the TCP connection beyond the processing of the individual request.
Options A and D are incorrect because they imply that the REST API is stateful, which contradicts the stateless nature of REST.
Reference: REST API Design Principles: Describes the stateless nature of REST and the responsibility of clients in managing session state.
Web Development Documentation: Discusses how REST APIs operate, focusing on statelessness and client-server interaction.