JNCIA-DevOps Python And PyEZ Practice Test 2 — 15 Questions

Question 1

When executing raw XML RPCs via PyEZ, which THREE approaches or parameters can be used to handle or inspect the response XML? (Choose two) -> Wait, let's make it THREE since the prompt requires HALF of multi-select to be 'Which THREE'. Let's verify prompt: 'HALF use 'Which TWO', HALF use 'Which THREE'.' Total multi-select = 6. 3 use TWO, 3 use THREE. Let's make this one THREE. Which THREE approaches...

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Using etree.tostring(response, encoding='unicode') to view raw XML text. RPC responses can be converted, queried with XPath, or printed as strings.

Answer

Using dev.rpc.to_dict() to automatically serialize all RPC outputs

Answer

Using json.loads() directly on the RPC response object

Question 2

You need to retrieve operational data from a Junos device using a PyEZ RPC call that equates to the CLI command 'show system information'. Which Python statement correctly invokes this RPC?

Accepted Answer

dev.rpc.get_system_information(). In PyEZ, CLI commands can be translated to RPC methods by converting dashes to underscores. 'show system information' becomes dev.rpc.get_system_information().

Answer

dev.execute("show system information")

Answer

dev.get_config(cli="show system information")

Answer

dev.rpc.show_system_information()

Question 3

When loading configuration changes via PyEZ using cu.load(format='xml', action='update'), what is the precise impact of the 'update' action compared to 'merge' or 'override'?

Accepted Answer

It merges configuration changes with the existing candidate configuration, modifying or adding specified nodes while preserving unreferenced nodes.. The 'update' action merges configuration elements based on matching keys or identifiers, allowing precise modification of existing hierarchical statements without replacing entire blocks.

Answer

It overwrites the entire candidate configuration, discarding all prior uncommitted changes.

Answer

It completely replaces the running configuration with the provided payload.

Answer

It deletes the matching hierarchy nodes entirely before inserting new ones.

Question 4

Which TWO of the following methods or attributes are valid ways to handle rollback operations or commit errors when using the PyEZ Config utility (cu)?

Accepted Answer

cu.rollback(id=1). Option B, cu.rollback(id=1), is correct because the PyEZ Config utility exposes a rollback() method that accepts an id parameter to load a previously committed configuration (rollback 1 is the last committed config) and restore it, which is the standard way to undo a bad change. Option D, cu.commit(comment="Automated deployment", timeout=30), is correct because commit() is the method that applies the candidate configuration, and it accepts a comment for the commit log and a timeout value to control how long to wait for the commit to complete, which is how you handle commit errors and ensure the operation finishes. Option A, cu.force_commit(), is not a valid PyEZ Config method; there is no such API. Option C, cu.undo(), does not exist in the PyEZ Config utility. Option E, cu.revert(rollback=0), is not a valid method signature; rollback is performed via cu.rollback(id=...) and rollback 0 is the current candidate, not a committed rollback point.

Answer

cu.force_commit()

Answer

cu.undo()

Answer

cu.revert(rollback=0)

Question 5

You are developing a PyEZ script that loads a configuration from a Jinja2 template and commits it. The template uses variables that must be provided. Which PyEZ method should you use to load the rendered configuration while also performing a syntax check before commit?

Accepted Answer

`dev.load(merge=True)` followed by `dev.commit_check()`. To load a configuration and perform a syntax check, you must call `load()` and then `commit_check()`. The `load()` method alone does not validate syntax. Using `commit_check()` after loading ensures errors are caught before committing, which is a best practice in automation.

Answer

`dev.load(overwrite=True)`

Answer

`dev.load()`

Answer

`dev.load(merge=True)`

Question 6

You are writing a PyEZ script to gather and manipulate operational data from a Junos device. You want to use the `Table` and `View` classes to parse the XML output into a structured format. Which two statements are correct about defining a custom `View` in PyEZ? (Choose two.)

Accepted Answer

The `View` class uses a dictionary called `fields` to map user-friendly field names to XPath expressions.. A PyEZ `View` defines a `fields` dictionary mapping names to XPath expressions, and it supports nested dictionaries for hierarchical data. These are key features for parsing XML into structured objects. The other statements are incorrect because `groups` is optional, XPath expressions are relative, and `__repr__` is not automatically tabular.

Answer

The `View` class automatically generates a `__repr__` method that displays all fields in a tabular format.

Answer

The `View` class requires that all XPath expressions in the `fields` dictionary be absolute paths starting with a forward slash.

Answer

The `View` class must inherit from `jnpr.junos.factory.view.View` and define a `groups` attribute for grouping fields.

Question 7

You are writing a PyEZ script that connects to a Junos device and loads a configuration snippet. You want to ensure the configuration is merged with the existing candidate configuration. Which method should you use on the Config object?

Accepted Answer

cu.load(path='config.conf', merge=True). To merge a configuration snippet with the existing candidate configuration, you set merge=True in the load method. This preserves existing configuration while adding or modifying statements from the snippet. Other parameters like overwrite or update serve different purposes and are not appropriate for a simple merge.

Answer

cu.load(path='config.conf', update=True)

Answer

cu.load(path='config.conf', replace=True)

Answer

cu.load(path='config.conf', overwrite=True)

Question 8

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

Accepted Answer

from jnpr.junos.utils.sw import SW. The SW utility module from jnpr.junos.utils.sw is used for software installation and upgrades.

Answer

from jnpr.junos.utils.upgrade import Upgrade

Answer

from jnpr.junos.utils.config import Config

Answer

from jnpr.junos.device import OS_Update

Question 9

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?

Accepted Answer

reboot=True. The PyEZ SW utility's install() method accepts a reboot=True parameter that instructs the utility to reboot the device automatically after the Junos image is successfully installed. This is the documented keyword argument in the jnpr.junos.utils.sw.SW class, and it triggers the device reboot as part of the install workflow.

Answer

auto_reboot=1

Answer

reload_after_install=True

Answer

action='reboot'

Question 10

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?

Accepted Answer

cu.load(path='interfaces.conf', format='text'). The Config object's load() method is the standard PyEZ API for loading configuration data into a candidate configuration, and it accepts a path argument pointing to an external file plus a format argument specifying the data format. Since the file is a plain text Junos configuration file, format='text' is the correct specification. This combination loads the file contents into the candidate config so it can later be committed.

Answer

dev.load_configuration(file='interfaces.conf')

Answer

cu.load_file('interfaces.conf')

Answer

cu.read_config('interfaces.conf')

Question 11

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?

Accepted Answer

dev.rpc.get_ethernet_switching_table_information(). PyEZ maps XML RPC hyphens to Python underscores, allowing you to call rpc methods directly as attributes on dev.rpc.

Answer

dev.rpc.get-ethernet-switching-table-information()

Answer

dev.get_ethernet_switching_table_information()

Answer

dev.execute_rpc('get-ethernet-switching-table-information')

Question 12

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?

Accepted Answer

dev.facts. The dev.facts property on a PyEZ Device instance returns a dictionary of standard hardware and OS inventory facts, such as hostname, model, serial number, Junos version, and uptime. It is populated automatically when the Device connects and is accessed as a property, not called as a method. This is the canonical way to retrieve inventory facts in PyEZ scripts.

Answer

dev.rpc.get_system_inventory()

Answer

dev.gather_facts()

Answer

dev.get_facts()

Question 13

You are writing a script that uses PyEZ to load a partial configuration merge. By default, what configuration database mode does the Config utility lock and load into?

Accepted Answer

The candidate configuration database. By default, PyEZ loads configuration changes into the candidate configuration database.

Answer

The rescue configuration database

Answer

A private configuration database instance

Answer

The global active configuration database

Question 14

An automation engineer is writing a Python script using Junos PyEZ to connect to a device. Which module and class must be imported to instantiate a device object representing the Junos target?

Accepted Answer

from jnpr.junos.device import Device. Junos PyEZ provides the Device class in the jnpr.junos.device module, which is used to instantiate a device object representing a Junos target. Importing 'from jnpr.junos.device import Device' is the correct way to create a Device instance and connect to a Junos device. This is the foundational import for any PyEZ automation script.

Answer

from jnpr.junos.rpcs import RPC

Answer

from jnpr.junos.facts import Facts

Answer

from jnpr.junos.utils.sw import SW

Question 15

What is the primary templating engine used alongside Python for generating structured Junos configuration text in network automation workflows?

Accepted Answer

Jinja2. Jinja2 is the de facto templating engine used with Python for generating Junos configuration text in network automation. It is bundled or easily installed alongside Python, integrates natively with Ansible, and supports loops, conditionals, and variable substitution that map cleanly to Junos configuration hierarchies. Its syntax ({{ }} for variables, {% %} for logic) is widely used in Junos automation examples and Juniper's own tooling.

Answer

Ansible Engine

Answer

Mako

Answer

ERB