JNCIA-DevOps Exam Questions and Answers

Which PyEZ utility module should you import if you need to upgrade the Junos operating system on a remote device via a Python script?

When managing configuration changes via PyEZ Config utility, which context manager ensures that changes are automatically rolled back if an exception occurs within the block?

You are using the PyEZ SW utility to install a new Junos image on a device. Which method parameter allows the script to automatically reboot the device after a successful installation?

An engineer is applying a candidate configuration using PyEZ and needs to load it from an external text file named 'interfaces.conf'. Which Config method should be used?

You need to execute a custom remote procedure call (RPC) in PyEZ to retrieve the Ethernet switching table. The tag in Junos XML API is get-ethernet-switching-table-information. How should you write this method call in Python?

You are writing a Python script to gather operational state information from a Junos device using PyEZ. Which method should you call on an open Device instance to retrieve standard hardware and OS inventory facts into a dictionary?

What is the primary benefit of using structured data formats (such as XML, JSON, or YAML) over unstructured CLI text output in Junos automation?

In a DevOps pipeline managing Junos devices, an engineer implements 'Infrastructure as Code' (IaC). Which practice best exemplifies this methodology when applied to Junos routing policies?

An engineer needs to explain the primary advantage of treating network configurations as code in a modern DevOps workflow. Which principle best describes this approach?

You are configuring a CI/CD pipeline for Junos network deployments. The pipeline must validate the syntax of generated candidate configurations against a physical or virtual Junos device before committing them to production. Which stage of the CI/CD pipeline does this validation step represent?

Your CI/CD pipeline includes a linters step before deployment. Why is running a linter against YAML or Jinja2 template files critical in a Junos automation workflow?

A network engineer is using Git for version control of Junos configurations. During a peer review on a pull request, a merge conflict arises because two engineers modified the same interface description line in different branches. What is the correct procedure to resolve this conflict in Git?

An automation script reads a multi-document YAML file containing configuration templates for various Junos router models. To process each document individually in Python using PyYAML, which function should the engineer invoke?

An engineer needs to represent an ordered list of IP addresses in a YAML configuration file for a Junos automation playbook. Which valid YAML syntax correctly defines a sequence of items?

A Python script retrieves interface statistics from a Junos device in JSON format, modifies a threshold value, and needs to output it back into a formatted JSON string with an indentation level of 4 spaces for readability. Which Python snippet achieves this?

An automation engineer is writing a Python script that takes a complex nested Python dictionary containing Junos telemetry parameters and converts it into a YAML string. Which PyYAML function should be used?

A network automation script is reading a YAML configuration file containing Junos device credentials. The script encounters an unhandled exception when attempting to load the file using PyYAML. Upon inspection, the error is caused by a tab character used for indentation instead of spaces. Which YAML specification rule does this violate?

You are writing a Python automation script that processes JSON output from a Junos device's 'show interfaces' operational command via PyEZ. One of the interface descriptions contains raw control characters. When the script attempts to dump this data to a JSON string using json.dumps(), it raises a ValueError. Which parameter should you pass to json.dumps() to handle non-printable or out-of-range character encoding gracefully?

Which NETCONF RPC tag is used to gracefully terminate an active NETCONF session with a Junos device?

While executing a NETCONF edit-config operation, you want to ensure that any syntax errors or invalid statements immediately cause the device to roll back the entire transaction without applying partial changes. Which parameter achieves this?

Which XML tag encapsulates the entire response returned by a Junos device in reply to a valid NETCONF RPC request?

You want to retrieve only the system hostname from the Junos running configuration using NETCONF. Which filtering technique is most efficient?

You need to lock the candidate configuration datastore in your NETCONF script to prevent concurrent modifications by other administrators. Which XML element accomplishes this?

You are writing a Python script to retrieve the operational state of interfaces from a Junos device using NETCONF. Which XML RPC element must be enclosed within the <rpc> tag to request operational data?

When executing a configuration change via the Junos REST API, what is the role of the HTTP DELETE method?

An administrator wishes to secure their Junos REST API connections by configuring HTTPS instead of plain HTTP. Which command under 'system services jpagent' accomplishes this?

Which data serialization formats are natively supported by the Junos REST API for both input and output payloads?

Which service daemon must be explicitly enabled in the Junos CLI configuration to allow REST API requests to be processed by the routing engine?

You are writing a Python script to retrieve interface statistics from a Junos device using the REST API. You use HTTP Basic Authentication. Which HTTP header must be included to pass the encoded credentials correctly?

An automation engineer is trying to retrieve operational data from a Junos device using the REST API. They send an HTTP GET request to the URI path 'http://192.168.1.1:3000/api/font/operational/system/information', but the request fails with a 404 Not Found error. What is the cause of this failure?