JNCIA-DevOps Practice Test 9 — 10 Questions

Question 1

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 2

In JSNAPy, what file format is used to define test cases and expected operational states?

Accepted Answer

YAML. JSNAPy uses YAML configuration files for defining tests and expected values.

Answer

INI

Answer

XML

Answer

JSON

Question 3

When serializing Python data structures to JSON for Junos automation payloads, which THREE parameters can be passed to json.dumps() to control formatting and readability? (Choose three)

Accepted Answer

separators. Option B, separators, is correct because json.dumps() accepts a (item_separator, key_separator) tuple that controls the characters placed between JSON elements, letting you produce compact output such as (',', ':') for smaller Junos payloads. Option C, sort_keys, is correct because setting sort_keys=True makes json.dumps() emit object keys in sorted order, which yields deterministic, diff-friendly JSON for configuration and automation scripts. Option E, indent, is correct because passing indent (for example indent=2 or indent=4) pretty-prints the JSON with newlines and that many spaces per level, improving readability of Junos payloads. Option A, max_depth, is not a valid json.dumps() parameter; Python's json module has no depth-limiting argument. Option D, strict_mode, is also not a json.dumps() parameter; the closest real argument is strict, which controls whether control characters inside strings are allowed, but 'strict_mode' itself does not exist.

Answer

max_depth

Answer

strict_mode

Question 4

During script development, an engineer encounters a YAML file containing comments and multiple configuration documents separated by document markers. Which characters are used to denote the start of a new document within a single YAML file stream?

Accepted Answer

---. In YAML, three dashes (---) indicate the start of a document, while three dots (...) indicate the end of a document.

Answer

===

Answer

...

Answer

###

Question 5

In a Junos NETCONF automation workflow, what happens during a lock operation on the configuration database? (Choose two)

Accepted Answer

Exclusive write access is acquired for the requesting session, preventing concurrent configuration modifications by other users or scripts.. Option A is correct because a Junos operation on the candidate configuration grants the requesting NETCONF session exclusive write access, so other users, CLI sessions, or automation scripts cannot modify the configuration concurrently until the lock is released. Option C is correct because the lock is held by that session and must be explicitly released with an operation, or implicitly released when the NETCONF session closes, before other processes can edit the configuration. The unmarked options are incorrect: B is false because locking the configuration database has nothing to do with powering down a Routing Engine, D is false because operational commands like 'show route' remain available and are not disabled by a configuration lock, and E is false because no firewall filters are deleted by a lock operation.

Answer

The physical routing engine is immediately powered down to prevent hardware wear.

Answer

All operational state monitoring (such as 'show route') is permanently disabled.

Answer

All firewall filters on all interfaces are automatically deleted.

Question 6

Which TWO tools or platforms are commonly used for version control and hosting of Junos automation code repositories? (Choose two)

Accepted Answer

GitHub. GitHub (C) is correct because it is a widely used web-based platform built on Git that provides repository hosting, branching, pull requests, and CI/CD integration for storing and collaborating on Junos automation code such as Python scripts, Jinja2 templates, and YAML playbooks. GitLab (E) is also correct because it is a Git-based DevOps platform offering self-managed or SaaS repository hosting, merge requests, and built-in CI/CD pipelines commonly used to manage and deploy Junos automation content. The remaining options do not belong: Adobe Photoshop (A) is an image-editing application, Microsoft Word (B) is a document word processor, and VLC Media Player (D) is a multimedia player — none of these provide Git-based version control or code repository hosting.

Answer

Adobe Photoshop

Answer

Microsoft Word

Answer

VLC Media Player

Question 7

An automation engineer is writing a Python script that retrieves the operational status of all interfaces from a Junos device using the Junos REST API. The script sends a GET request to https://device/rest/interface. The device returns an HTTP 200 OK response, but the response body is empty. The engineer examines the request and confirms that the URL is correct and the device is reachable. Which action should the engineer take to retrieve the interface status information?

Accepted Answer

Use the correct RPC endpoint, such as /rest/rpc/get-interface-information, to retrieve operational data.. The Junos REST API provides access to operational data through RPCs, not through arbitrary REST endpoints. To retrieve interface status, the correct endpoint is /rest/rpc/get-interface-information. A GET request to /rest/interface does not correspond to a valid RPC and returns an empty body. Using the proper RPC endpoint ensures the desired operational information is returned in the response.

Answer

Add the Accept: application/json header to the request.

Answer

Change the HTTP method to POST and include a JSON payload specifying the interface names.

Answer

Append the query parameter ?type=operational to the URL.

Question 8

When using Jinja2 templates in Python to generate configurations, how can you load a template file from disk prior to rendering it with variables?

Accepted Answer

Template(open('template.j2').read()). The Jinja2 `Template` class accepts a template source string, so reading the file contents with `open('template.j2').read()` and passing that string to `Template()` is a valid way to load a template from disk. This is the standard minimal pattern when you don't need Jinja2's file-system loader features. The other options reference methods or modules that do not exist in the Jinja2 API.

Answer

template.open('template.j2')

Answer

import_template('template.j2')

Answer

jinja2.load_file('template.j2')

Question 9

A network automation developer is writing a Python script that uses the Junos REST API to load a candidate configuration from a file and commit it. The developer wants to ensure the configuration is merged with the existing candidate configuration. Which HTTP method and endpoint should be used to load the configuration?

Accepted Answer

POST to /rest/conf/ with the configuration in the request body. To load configuration into the candidate configuration via the Junos REST API, an automation script sends an HTTP POST request to the /rest/conf/ endpoint with the configuration data in the request body. This operation defaults to a merge load, combining the new configuration with the existing candidate. Other methods like PUT or GET are not used for configuration loading.

Answer

GET to /rest/conf/ with the configuration as a query parameter

Answer

POST to /rest/config/ with the configuration in the request body

Answer

PUT to /rest/conf/ with the configuration in the request body

Question 10

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