JNCIA-DevOps Junos Automation Stack And DevOps Concepts Practice Test 4 — 15 Questions

Question 1

Which TWO characteristics describe declarative network automation compared to imperative scripting? (Choose two)

Accepted Answer

Defining the desired end state rather than scripting exact step-by-step CLI commands. Declarative automation defines the desired state, leaving the system to determine how to reach it, whereas imperative scripts specify exact steps.

Answer

Manually logging into each router to execute sequential shell commands

Answer

Using hardcoded assembly language for packet processing

Answer

Requiring manual calculation of diff patches for every single line item

Question 2

Which THREE tasks are typical responsibilities of a network DevOps engineer managing a Junos infrastructure? (Choose three)

Accepted Answer

Writing and maintaining Python automation scripts and Jinja2 templates. DevOps engineers write automation code, build CI/CD pipelines, and manage version control systems.

Answer

Manually crimping CAT6 Ethernet cables in the wiring closet

Answer

Manually rebooting every switch in the data center daily

Question 3

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.. Locking a configuration database prevents other users or processes from making conflicting changes until unlocked.

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 4

An automation engineer is designing a Junos network automation workflow and needs to select the component of the Junos automation architecture responsible for parsing XML and JSONRPC client requests and interacting directly with the Junos kernel and daemons. Which component fulfills this role?

Accepted Answer

mgd (Management Daemon). MGD (Management Daemon) is the primary user interface handler in Junos OS. It processes CLI commands, Netconf XML requests, and JSON-RPC APIs, translating them into operations interacting with the Junos kernel and individual routing daemons via RRDS.

Answer

jails

Answer

rpd (Routing Protocol Daemon)

Answer

jsd (Junos Script Daemon)

Question 5

A network engineer is establishing a version control workflow for network configurations using Git. Which Git command should the engineer use to stage newly created configuration template files in the local repository working directory so they are included in the next commit?

Accepted Answer

git add. The git add command stages changes in the working directory, moving them to the staging area (index) to prepare them for a commit.

Answer

git clone

Answer

git commit

Answer

git push

Question 6

An operations team is applying DevOps principles to network automation on Junos devices. They want to ensure that all changes to device operational states and configurations are treated as disposable and repeatable. Which DevOps practice best describes rebuilding device configurations completely from centralized version-controlled templates rather than performing manual incremental hot-patches?

Accepted Answer

Immutable infrastructure and declarative provisioning. Infrastructure as Code (IaC) and immutable infrastructure treat configurations as reproducible artifacts generated from source control rather than mutable, long-lived states modified ad-hoc.

Answer

Stateful configuration drift management

Answer

Blue-green circuit provisioning

Answer

Event-driven telemetry ingestion

Question 7

A DevOps engineer is implementing a CI/CD pipeline for automated testing of Junos configurations. During the build stage, the pipeline executes a syntax check on candidate configurations before staging them for deployment. Which tool natively provides configuration syntax validation against the Junos schema without applying the configuration to the routing engine?

Accepted Answer

Junos PyEZ configuration mode via the 'cu.validate()' method. The Junos PyEZ library provides a configuration management module that allows validation of candidate configurations locally or on the device using validate() without committing changes.

Answer

Ansible junipernetworks.junos.junos_config module with 'check_mode: true'

Answer

SaltStack junos.commit execution module

Answer

git-lfs configuration validator

Question 8

A network automation engineer is writing a Python script using the Junos PyEZ library to retrieve operational state from a QFX Series switch. The script needs to retrieve interface statistics using an RPC instead of raw CLI text parsing. Which PyEZ method should the engineer execute to invoke the 'get-interface-information' RPC and receive the structured XML response?

Accepted Answer

dev.rpc.get_interface_information(). In Junos PyEZ, the dev.rpc() method is used to execute native Junos XML RPCs directly against the device and return the results as an ElementTree XML object.

Answer

dev.get_config(format='xml')

Answer

dev.load(action='set', format='xml')

Answer

dev.execute_cli('show interfaces')

Question 9

An enterprise network is adopting a CI/CD pipeline for Junos network changes using GitLab CI. A developer wants to ensure that a test job automatically runs whenever a merge request is opened against the main branch. In which configuration file must this pipeline behavior be defined, and what is the primary keyword used to control branch execution?

Accepted Answer

.gitlab-ci.yml, using the 'rules' or 'only' keyword. GitLab CI pipelines are defined in a .gitlab-ci.yml file located in the root of the repository, and jobs use the 'rules' or 'only/except' keywords to control execution on specific branches.

Answer

Junos 'juniper.conf', using the 'commit-script' keyword

Answer

ansible.cfg, using the 'hosts' parameter

Answer

Jenkinsfile, using the 'when' parameter

Question 10

A network architect is designing a version control strategy for multi-vendor network operations. They need a system that tracks changes to text-based configuration files, allows multiple engineers to work on separate feature branches concurrently, and merges changes systematically. Which category of tool is being utilized?

Accepted Answer

Distributed Version Control System (DVCS). Git and similar tools are Distributed Version Control Systems (DVCS) designed to track file revisions and manage collaborative workflows through branching and merging.

Answer

Network Management System (NMS) poller

Answer

Network Configuration Protocol (NETCONF) manager

Answer

Dynamic Host Configuration Protocol (DHCP) server

Question 11

An engineer is automating Junos device deployments using Ansible. They need to push a set of hierarchical configuration changes to a cluster of MX Series routers and ensure the changes are committed only if there are no syntax errors, while keeping the connection open for subsequent tasks. Which Ansible module and parameter combination should be used?

Accepted Answer

junipernetworks.junos.junos_config with 'update: merge' and 'diff: true'. The junipernetworks.junos.junos_config module manages Junos configurations, and the 'confirm' or 'diff' parameters manage operational validation, while the transport connection is handled automatically by the collection.

Answer

junipernetworks.junos.junos_command with 'commands: ["configure", "commit check"]'

Answer

ansible.builtin.template with 'dest: /config/juniper.conf'

Answer

netconf_config with 'provider: junos'

Question 12

A network engineer is exploring the core components of the Junos automation architecture. Which TWO components are native Junos daemons or automation frameworks directly involved in script execution or API processing? (Choose TWO)

Accepted Answer

jsd (Junos Script Daemon). jsd (Junos Script Daemon) executes local SLAX and Python event scripts, and mgd (Management Daemon) processes XML/NETCONF/JSON-RPC automation requests.

Answer

snmpd (Simple Network Management Protocol Daemon)

Answer

sshd (Secure Shell Daemon)

Answer

httpd (Hypertext Transfer Protocol Daemon)

Question 13

An organization is implementing a Git-based version control strategy for Junos network configurations. Which THREE practices are considered standard DevOps workflows when managing network configurations in Git? (Choose THREE)

Accepted Answer

Tagging specific repository commits to mark official production releases or maintenance versions. Standard Git workflows involve storing configurations as plain text templates, using pull/merge requests for peer review before merging, and tagging repository commits corresponding to official maintenance windows or production releases.

Answer

Directly committing experimental production changes to the master branch without review

Answer

Encrypting all configuration text files using binary compressed archives inside Git

Question 14

A DevOps engineer is designing a CI/CD pipeline for validating Junos configuration changes prior to deployment. Which THREE actions are typically performed during the automated CI pipeline 'test' or 'validate' stage? (Choose THREE)

Accepted Answer

Performing dry-run validation checks against staging or virtual Junos instances (vSRX). CI validation stages typically run linting checks, static syntax validation against Junos schemas, and unit testing of templates or automation code before deployment staging.

Answer

Immediately rebooting the production core routing engine to apply all updates

Answer

Manually logging into physical CLI consoles to troubleshoot cabling

Question 15

A network automation engineer is utilizing the Junos PyEZ library in Python to manage device configurations. Which THREE methods or classes are part of the core Junos PyEZ library functionality? (Choose THREE)

Accepted Answer

ConnectError exception for handling connection failures to the device. Junos PyEZ provides the Device class for connection management, the Config table/view context manager for configuration transactions, and exception handling classes like ConnectError.

Answer

Docker container orchestration module for spinning up microservices

Answer

Playbook execution engine for running local bash shell scripts