CCNA Junos Automation Stack And DevOps Concepts Questions

MCQmedium

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.To compile YAML files into Junos microcode for the Packet Forwarding Engine.

B.To automatically execute unit tests against live BGP peering sessions.

C.To detect syntax errors, indentation issues, and style violations in template and data files before deployment.

D.To encrypt sensitive passwords stored within plaintext configuration files.

AnswerC

Correct. Linters validate static code and markup syntax prior to runtime execution.

Why this answer

Linters catch syntax errors, formatting inconsistencies, and indentation mistakes before files are processed by automation tools or sent to devices.

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Multi-Selectmedium

Which THREE mechanisms are valid methods for authenticating and establishing a NETCONF session with a Junos device? (Choose three)

Select 3 answers

A.Remote RADIUS or TACACS+ AAA server integration via SSH transport

B.Username and password authentication over SSH

C.SSH public key authentication

D.Anonymous guest access without credentials

E.Unencrypted cleartext Telnet on TCP port 23

AnswersA, B, C

Correct. Junos supports AAA for NETCONF/SSH sessions.

Why this answer

NETCONF on Junos runs over SSH, supporting SSH keys, username/password, and AAA integration.

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MCQmedium

In the context of network DevOps, what is the purpose of implementing idempotency in automation scripts or playbooks targeting Junos devices?

A.To ensure that running the same configuration task multiple times produces the exact same desired state without making redundant changes if already applied.

B.To encrypt all configuration payloads using AES-256 before transport.

C.To ensure that every script execution generates a completely random new configuration to test device resilience.

D.To force the Junos Routing Engine to reboot every time a script is executed.

AnswerA

Correct. Idempotent operations can be run repeatedly with safe, predictable outcomes.

Why this answer

Idempotency ensures that running the same automation task multiple times yields the same result without making unintended changes if the state is already correct.

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Multi-Selecteasy

Which TWO advantages does structured telemetry and data streaming offer over traditional SNMP polling in Junos automation? (Choose two)

Select 2 answers

A.Requiring all network devices to run Windows Server OS

B.Mandatory requirement for analog dial-up modems

C.High granularity and real-time visibility into operational state

D.Elimination of all network interfaces

E.Push-based streaming model instead of periodic polling overhead

AnswersC, E

Correct. Telemetry provides fine-grained, real-time data.

Why this answer

Streaming telemetry provides real-time push-based data with high granularity, avoiding the polling overhead of SNMP.

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MCQhard

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?

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

B.ansible.cfg, using the 'hosts' parameter

C.Jenkinsfile, using the 'when' parameter

D..gitlab-ci.yml, using the 'rules' or 'only' keyword

AnswerD

GitLab CI uses .gitlab-ci.yml and controls branch triggers using keywords such as rules or only.

Why this answer

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.

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Multi-Selecthard

In a Git repository managing Junos configurations, which TWO files or directories are typically added to the '.gitignore' file to prevent sensitive or temporary files from being tracked? (Choose two)

Select 2 answers

A.Core YANG data models provided by Juniper

B.Local IDE configuration folders and temporary build output directories

C.Master branch commit history logs

D.Files containing decrypted production passwords or private SSH keys

E.Standard production Jinja2 templates (.j2)

AnswersB, D

Correct. IDE artifacts and temp outputs should be ignored.

Why this answer

.gitignore should exclude temporary build files, secret key files, and IDE-specific settings.

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MCQhard

An automation engineer is using Git and needs to undo the last local commit while keeping the modified changes in their working directory as unstaged changes. Which command should they execute?

A.git reset --hard HEAD~1

B.git checkout -f master

C.git reset HEAD~1 (or git reset --mixed HEAD~1)

D.git revert --purge

AnswerC

Correct. git reset HEAD~1 keeps the working tree changes intact while undoing the commit.

Why this answer

'git reset --soft HEAD~1' or 'git reset HEAD~1' resets the commit while keeping working tree files modified/staged depending on flags. 'git reset HEAD~1' defaults to mixed (keeps changes unstaged).

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MCQmedium

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?

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

B.SaltStack junos.commit execution module

C.Junos PyEZ configuration mode via the 'cu.validate()' method

D.git-lfs configuration validator

AnswerC

The PyEZ cu.validate() method checks the candidate configuration against the device syntax and semantic rules.

Why this answer

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.

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Multi-Selecteasy

Which TWO benefits are provided by implementing automated CI/CD pipelines for Junos network changes? (Choose two)

Select 2 answers

A.Standardized, repeatable validation and testing of every change before production

B.Elimination of network routing protocols like OSPF

C.Immediate physical replacement of broken optical transceivers by robots

D.Accelerated deployment speed and reduced human configuration errors

E.Guaranteed 100% uptime regardless of fiber cuts

AnswersA, D

Correct. Automated testing ensures consistency.

Why this answer

CI/CD provides faster delivery, automated error checking, reduced manual toil, and consistent deployments.

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MCQmedium

An automation script connects to a Junos device and attempts to load a candidate configuration using NETCONF. The script needs to ensure that if any part of the configuration fails validation, the entire transaction is discarded and the candidate database is left untouched. Which NETCONF capability or tag should be utilized?

A.The SNMP trap notification daemon running on port 162

B.The <rollback> RPC with an explicit configuration revision number

C.The 'cli -s' force-override flag in an SSH execution session

D.The candidate configuration database lock combined with atomic transaction semantics provided by NETCONF <lock> and <commit> operations.

AnswerD

Correct. NETCONF provides atomic transaction capabilities where the candidate configuration is verified and committed atomically.

Why this answer

NETCONF supports robust transaction handling, ensuring that configuration changes are validated as a block and rolled back on error.

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Multi-Selecteasy

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

Select 2 answers

A.Manually logging into each router to execute sequential shell commands

B.Defining the desired end state rather than scripting exact step-by-step CLI commands

C.Using hardcoded assembly language for packet processing

D.Requiring manual calculation of diff patches for every single line item

E.The automation engine automatically computes and applies the required changes to reach the goal

AnswersB, E

Correct. Declarative tools focus on what state to achieve.

Why this answer

Declarative automation defines the desired state, leaving the system to determine how to reach it, whereas imperative scripts specify exact steps.

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MCQhard

An enterprise uses Git for tracking Junos configurations. An engineer wants to see the exact line-by-line history of changes made to a specific routing policy file over the past month, including who made each change. Which Git command should they use?

A.git blame <filename> or git log -p <filename>

B.git history --routing-policy

C.git diff --author

D.git status --verbose

AnswerA

Correct. 'git blame' shows line authorship, and 'git log -p' shows patch/diff history per file.

Why this answer

'git blame' shows what revision and author last modified each line of a file, while 'git log' shows commit history.

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MCQmedium

Why is it considered a best practice to store sensitive secrets (such as SNMP community strings or API tokens) outside of plaintext Jinja2 templates in a Git repository?

A.Because Junos devices do not accept authentication strings longer than 8 characters.

B.To prevent Jinja2 rendering engines from running out of memory.

C.To ensure that NETCONF sessions always default to unencrypted plain text.

D.To prevent unauthorized exposure of credentials in shared version control systems, utilizing secure secret management tools instead.

AnswerD

Correct. Version control history is public/shared among teams, so secrets should be encrypted or managed externally.

Why this answer

Storing secrets in plaintext in version control risks exposure of sensitive credentials to anyone with repository access.

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MCQeasy

Which term describes the practice of continuously building, testing, and validating software or network configurations in an automated pipeline?

A.CI/CD (Continuous Integration / Continuous Deployment)

B.Manual Change Advisory Board (CAB) review

C.Cold-boot disaster recovery

D.Static physical cable patching

AnswerA

Correct. CI/CD automates integration, testing, and deployment.

Why this answer

Continuous Integration / Continuous Deployment (CI/CD) describes automated building and testing.

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Multi-Selecthard

When interacting with Junos devices via NETCONF, which TWO RPC operations are part of standard NETCONF protocol capabilities? (Choose two)

Select 2 answers

A.<reboot-routing-engine-force>

B.<get-config>

C.<format-hard-drive>

D.<traceroute-packet>

E.<edit-config>

AnswersB, E

Correct. <get-config> retrieves configuration data.

Why this answer

NETCONF standard operations include <get-config>, <edit-config>, <commit>, <lock>, etc.

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MCQeasy

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?

A.Immutable infrastructure deployment where devices are replaced rather than updated manually.

B.Compiling the network CLI commands into binary machine code before executing them on Junos devices.

C.Storing configurations in a version control system to track history, enable rollbacks, and facilitate collaboration.

D.Automating the complete removal of the command-line interface in favor of graphical topology builders.

AnswerC

Correct. Network as code emphasizes version control systems (VCS) like Git for tracking history and peer review.

Why this answer

Treating network configurations as code allows infrastructure to be version-controlled, repeatedly deployed, and tested just like software code.

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MCQeasy

Which protocol is natively used by Junos XML management APIs to provide structured, session-oriented configuration and operational data exchange?

A.FTP

B.NETCONF

C.Syslog

D.Telnet

AnswerB

Correct. NETCONF is the foundational protocol for Junos structured management.

Why this answer

NETCONF is the session-oriented protocol used for Junos XML management.

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Multi-Selectmedium

When designing a version control workflow for Junos configurations using Git, which THREE practices are considered industry best standards? (Choose three)

Select 3 answers

A.Completely bypassing automated testing to speed up deployments

B.Using feature branches for developing new configuration changes before merging into main

C.Storing plaintext administrative passwords directly in public Git repositories

D.Requiring peer reviews and pull request approvals prior to merging changes

E.Using semantic or descriptive commit messages to document the intent of configuration updates

AnswersB, D, E

Correct. Feature branches isolate work in progress.

Why this answer

Best practices include code reviews via pull requests, using feature branches, and keeping secrets out of code.

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MCQeasy

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?

A.Network Management System (NMS) poller

B.Network Configuration Protocol (NETCONF) manager

C.Distributed Version Control System (DVCS)

D.Dynamic Host Configuration Protocol (DHCP) server

AnswerC

DVCS tools like Git manage source code and configuration history across distributed repositories.

Why this answer

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

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MCQhard

You are reviewing a pull request that updates Junos interface configurations using Jinja2 templates. The template contains a conditional statement checking an interface speed variable. What happens if the variable is undefined during template rendering?

A.The Git repository automatically rejects the push citing syntax errors.

B.Jinja2 raises an undefined error and halts template rendering unless default filters or conditional checks are used.

C.Junos automatically ignores the missing variable and applies default factory settings.

D.The target Junos router enters rescue mode due to corrupted NETCONF RPC messages.

AnswerB

Correct. Jinja2 throws an error on undefined variables unless explicitly handled.

Why this answer

Jinja2 raises an UndefinedError by default when an undefined variable is evaluated in a template, unless configured otherwise or handled with defined tests.

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Multi-Selectmedium

When writing Python automation scripts for Junos using PyEZ, which THREE objects or methods are commonly used for device interaction and configuration management? (Choose three)

Select 3 answers

A.Microsoft_Excel_Workbook for direct spreadsheet parsing

B.Kernel_Panic_Trigger to deliberately crash the router

C.Config (from jnpr.junos.utils.config) to handle configuration transactions

D.Fact (from jnpr.junos.factory.factory_Loader) to gather device hardware and software inventory

E.Device (from jnpr.junos) to manage the NETCONF connection session

AnswersC, D, E

Correct. Config manages locking, loading, committing, and rollbacks.

Why this answer

PyEZ uses Device for connections, Config for configuration management, and Fact for system information.

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MCQmedium

In a CI/CD pipeline for network changes, what is the role of automated unit testing?

A.To measure the exact fiber cable distance between two data centers.

B.To automatically upgrade the Junos OS kernel on all cluster nodes simultaneously.

C.To physically test the optical transceiver power levels using laser beams.

D.To verify that individual configuration modules, templates, or script functions produce expected outputs before integration.

AnswerD

Correct. Unit tests validate specific components in isolation.

Why this answer

Unit testing validates individual components (like a specific macro, template, or script function) to ensure they produce the expected output.

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MCQeasy

What is a primary characteristic of a DevOps culture when applied to network operations (NetOps)?

A.Siloing network operations strictly away from software development teams.

B.Eliminating all documentation in favor of verbal communication.

C.Emphasizing collaboration, automation, continuous testing, and shared responsibility between network and development teams.

D.Relying entirely on manual change approval boards for every minor configuration change.

AnswerC

Correct. DevOps fosters cross-functional collaboration and automation.

Why this answer

NetOps applies DevOps principles like collaboration, automation, and CI/CD to network engineering.

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MCQmedium

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?

A.Continuous Deployment stage

B.Continuous Integration validation stage

C.Continuous Monitoring stage

D.Infrastructure Provisioning stage

AnswerB

Correct. Validating candidate configurations without committing them is part of CI testing.

Why this answer

Checking syntax and logic prior to production deployment is a core part of the Continuous Integration (CI) validation and testing stage.

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MCQeasy

Which command is used in Git to save staged changes to the local repository with a descriptive commit message?

A.git add

B.git push

C.git commit -m "message"

D.git save

AnswerC

Correct. git commit records the staged snapshot with a message.

Why this answer

'git commit' records changes to the local repository.

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Multi-Selectmedium

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)

Select 3 answers

A.Tagging specific repository commits to mark official production releases or maintenance versions

B.Directly committing experimental production changes to the master branch without review

C.Storing network device configuration templates as plain text files in a repository

D.Submitting configuration changes through pull requests or merge requests for peer review

E.Encrypting all configuration text files using binary compressed archives inside Git

AnswersA, C, D

Git tags provide immutable reference points for specific production-deployed configuration states.

Why this answer

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.

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MCQhard

During a NETCONF session with a Junos device, an automation script issues an RPC to load a configuration. The device returns a response containing an <rpc-error> tag. What does this indicate?

A.The Junos routing engine is operating at 100% CPU capacity.

B.The NETCONF session has successfully terminated with a normal exit code.

C.The physical optical link on the management port has failed.

D.The configuration or RPC request failed validation, syntax checking, or execution constraints on the device.

AnswerD

Correct. <rpc-error> signals a failure in processing the request.

Why this answer

An <rpc-error> tag in NETCONF indicates that the request could not be processed successfully due to syntax, permission, or validation errors.

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MCQeasy

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?

A.git clone

B.git commit

C.git push

D.git add

AnswerD

git add stages new or modified files for the next commit.

Why this answer

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

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MCQmedium

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?

A.Stateful configuration drift management

B.Blue-green circuit provisioning

C.Immutable infrastructure and declarative provisioning

D.Event-driven telemetry ingestion

AnswerC

Declarative provisioning and immutable approaches replace manual hot-patches with clean, version-controlled configuration generation.

Why this answer

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.

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Multi-Selecthard

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)

Select 3 answers

A.Performing dry-run validation checks against staging or virtual Junos instances (vSRX)

B.Immediately rebooting the production core routing engine to apply all updates

C.Running automated linters and style checks on Python automation scripts and Jinja2 templates

D.Executing static syntax and semantic validation of candidate configurations against device schemas

E.Manually logging into physical CLI consoles to troubleshoot cabling

AnswersA, C, D

Testing against virtual instances (vSRX) validates behavior against real Junos parsing logic.

Why this answer

CI validation stages typically run linting checks, static syntax validation against Junos schemas, and unit testing of templates or automation code before deployment staging.

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Multi-Selectmedium

Which THREE principles are foundational to the DevOps movement when applied to network engineering? (Choose three)

Select 3 answers

A.Continuous monitoring and feedback loops for network telemetry

B.Strict siloing of operational teams from software developers

C.Relying solely on annual manual network audits

D.Culture of shared responsibility and rapid learning from failures

E.Automation of repetitive provisioning and configuration tasks

AnswersA, D, E

Correct. Monitoring provides feedback on changes and health.

Why this answer

Foundational DevOps principles include automation, continuous feedback, culture/collaboration, and transparency.

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Multi-Selecteasy

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)

Select 2 answers

A.jsd (Junos Script Daemon)

B.snmpd (Simple Network Management Protocol Daemon)

C.sshd (Secure Shell Daemon)

D.mgd (Management Daemon)

E.httpd (Hypertext Transfer Protocol Daemon)

AnswersA, D

jsd is responsible for running local automation scripts on Junos devices.

Why this answer

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

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MCQeasy

Which Junos automation architecture component provides standardized, model-driven interfaces using NETCONF and gRPC/gNMI to manage and monitor Junos devices?

A.The Junos CLI pipe filter 'match' command

B.Junos XML API and schema definitions

C.Proprietary screen-scraping CLI scripts running in a crontab daemon

D.The physical console cable attached to the Routing Engine

AnswerB

Correct. Junos XML API via NETCONF and RPCs provides structured data modeling.

Why this answer

Junos API and data modeling components like NETCONF and gRPC provide structured, programmatic access to the Junos control plane.

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Multi-Selectmedium

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

Select 3 answers

A.Manually crimping CAT6 Ethernet cables in the wiring closet

B.Writing and maintaining Python automation scripts and Jinja2 templates

C.Managing Git repositories, branch policies, and pull request workflows

D.Configuring and maintaining CI/CD pipeline tools (e.g., GitLab CI, GitHub Actions)

E.Manually rebooting every switch in the data center daily

AnswersB, C, D

Correct. Scripting and templating are core tasks.

Why this answer

DevOps engineers write automation code, build CI/CD pipelines, and manage version control systems.

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MCQmedium

When managing Junos configuration changes in a team environment, why is atomic configuration rollback capability crucial during automated deployments?

A.It compresses the configuration database to save NVRAM storage space.

B.It allows the router to dynamically rewrite Python scripts into C++ for faster execution.

C.It automatically backs up the entire Junos OS image to an external TFTP server.

D.It ensures that either all configuration statements in a transaction are applied successfully or none are, preventing partial/corrupt states.

AnswerD

Correct. Atomicity guarantees all-or-nothing transaction execution.

Why this answer

Atomic rollbacks ensure that if a change set fails validation or causes a network fault, the system can revert cleanly to the previous working state without partial application.

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MCQeasy

What is the primary function of a version control system (VCS) like Git in a Junos automation workflow?

A.To track configuration history, enable collaboration, and provide a single source of truth for network designs.

B.To act as a high-speed packet forwarding engine for BGP routes.

C.To compile Python automation scripts into binary executables.

D.To monitor real-time CPU utilization on Junos routing engines.

AnswerA

Correct. VCS provides history tracking, collaboration, and a source of truth.

Why this answer

A VCS tracks changes over time, enabling collaboration, rollback, and audit trails.

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Multi-Selectmedium

In a CI/CD pipeline configured for Junos network changes, which THREE automated testing steps are typically performed before production deployment? (Choose three)

Select 3 answers

A.Physical replacement of router power supply units

B.Manual approval of physical fiber patch cables by a security guard

C.Static code linting of YAML data and Jinja2 templates

D.Dry-run candidate configuration validation on a test Junos device or virtual instance

E.Automated schema validation against YANG models

AnswersC, D, E

Correct. Linting catches formatting and syntax errors.

Why this answer

Pipelines typically include syntax validation, schema validation, and dry-run commit checks.

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Multi-Selecthard

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

Select 2 answers

A.Exclusive write access is acquired for the requesting session, preventing concurrent configuration modifications by other users or scripts.

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

C.An unlock operation must be performed (or session closed) to release the lock for other processes.

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

E.All firewall filters on all interfaces are automatically deleted.

AnswersA, C

Correct. Locking prevents race conditions.

Why this answer

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

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Multi-Selecteasy

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

Select 2 answers

A.Adobe Photoshop

B.Microsoft Word

C.GitHub

D.VLC Media Player

E.GitLab

AnswersC, E

Correct. GitHub is a leading Git repository hosting platform.

Why this answer

Git is the standard version control system, hosted on platforms like GitHub or GitLab.

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Multi-Selecteasy

Which TWO file formats are commonly used for structuring network configuration data and automation templates in Junos DevOps pipelines? (Choose two)

Select 2 answers

A.JSON

B.YAML

C.Proprietary binary core dump format

D.Raw bitmap image (.bmp) format

E.Windows executable (.exe) format

AnswersA, B

Correct. JSON is widely used for structured data exchange.

Why this answer

YAML and JSON are standard data serialization formats used alongside Jinja2 templates.

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MCQmedium

An engineer wants to inspect the differences between two committed configurations on a Junos device using the CLI or automation tools. Which operation does this correspond to in Junos configuration management?

A.Running a traceroute across the management network

B.Comparing configuration revisions (e.g., rollback comparison) to audit modifications before committing.

C.Performing a NETCONF <discard-changes> operation

D.Reloading the Junos kernel image

AnswerB

Correct. Configuration comparison allows auditing differences between revisions.

Why this answer

Comparing configuration revisions is done using comparison features (e.g., 'show configuration | compare').

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MCQmedium

In a Junos automation environment, what role does a schema (such as YANG or Junos XSD) play when interacting with NETCONF?

A.It encrypts the communication channel between the client and the Junos device.

B.It defines the structural rules, data types, and valid hierarchy for configuration and operational data models.

C.It acts as a firewall filter blocking unauthorized IP addresses on the management interface.

D.It compiles Python scripts into executable machine code for the Routing Engine CPU.

AnswerB

Correct. Schemas define the valid structure of XML/JSON data.

Why this answer

YANG or XSD schemas define the data model structure, types, and constraints for configuration and operational data.

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MCQhard

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?

A.Reboot the Junos routing engine to clear the Git repository cache and force a fast-forward merge.

B.Run the 'git force-merge' command to automatically discard the older branch's changes.

C.Use 'git reset --hard' on the remote repository to delete both conflicting branches entirely.

D.Manually edit the conflict markers in the affected configuration file, stage the resolved file, and complete the merge commit.

AnswerD

Correct. Merge conflicts require manual intervention using conflict markers (<<<<, ====, >>>>), then staging and committing.

Why this answer

Git marks the conflicting lines in the file, requiring manual editing to choose the correct changes or combine them, followed by staging and committing the resolution.

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MCQmedium

What is the primary benefit of decoupling network configuration data (YAML/JSON) from presentation templates (Jinja2) in network automation?

A.It allows non-engineers to modify device variables without altering the core template logic, promoting the DRY principle.

B.It eliminates the need for any version control system.

C.It converts all configuration files into binary format to save disk space.

D.It forces the Junos device to run all configuration commits in parallel across all line cards.

AnswerA

Correct. Data/template separation allows reuse and simplifies updates.

Why this answer

Separating data from templates allows the same template to be reused across multiple devices with different data sets, adhering to DRY principles.

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MCQhard

A network engineer writes a Python script using Junos PyEZ to push a configuration change. The script uses the ConfigTable or Config class. What mechanism does PyEZ use under the hood to ensure the configuration lock is released even if the script encounters an unhandled exception?

A.NETCONF keepalive timers that drop the SSH session after 1 second.

B.A UNIX cron job that reboots the router every 5 minutes.

C.Python context managers ('with' statements) that automatically release locks and clean up session state upon exit.

D.Hardware watchdog timers built into the Routing Engine ASIC.

AnswerC

Correct. PyEZ configuration context managers ensure proper cleanup and lock release.

Why this answer

Python context managers (using the 'with' statement) automatically handle acquiring and releasing locks and rolling back candidate changes on exception in PyEZ.

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MCQeasy

Which Junos automation toolset relies heavily on XML over NETCONF and provides robust Python libraries tailored specifically for Junos network devices?

A.Junos PyEZ

B.Cisco IOS XE Embedded Event Manager (EEM)

C.Microsoft PowerShell Active Directory module

D.Arista eAPI Python client library

AnswerA

Correct. PyEZ is Juniper's Python library for Junos automation.

Why this answer

Junos PyEZ is the Python library tailored specifically for Junos devices using NETCONF.

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MCQhard

An automation pipeline tests Junos configuration changes against a virtual Junos device (such as vSRX or cRPD) in a CI environment before deploying to physical hardware. What is this practice called?

A.Production traffic shedding

B.Virtual staging and pre-deployment validation testing

C.Static code linting

D.Hardware refactoring

AnswerB

Correct. Using virtual network functions in CI pipelines validates changes safely before production.

Why this answer

Testing against virtualized network functions in a staging or CI environment is known as lab validation or digital twinning/staging.

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Multi-Selecthard

Which TWO components are essential parts of a model-driven network automation architecture on Junos devices? (Choose two)

Select 2 answers

A.YANG data models defining the structure and constraints of configuration and state data

B.Standardized management protocols such as NETCONF or gRPC/gNMI

C.Manual terminal emulation sessions using Telnet

D.Proprietary screen-scraping PERL scripts parsing raw CLI text

E.Physical serial port multiplexers

AnswersA, B

Correct. YANG models define structured data schemas.

Why this answer

Model-driven architecture relies on structured data models (YANG) and standardized transport protocols (NETCONF, gRPC).

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Multi-Selecteasy

Which TWO benefits are gained by applying DevOps principles to Junos network management? (Choose two)

Select 2 answers

A.Elimination of all network documentation requirements

B.Mandatory requirement for physical console cables on every device

C.Consistent, repeatable deployments through automation and version control

D.Exclusive reliance on manual CLI configuration commands

E.Improved collaboration and shared ownership between network and software engineering teams

AnswersC, E

Correct. Version control and automation ensure repeatability.

Why this answer

DevOps brings increased agility, faster deployments, better visibility, and reduced human error through automation and version control.

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MCQhard

An automation engineer is designing a deployment strategy for Junos devices using Git branches. Which branching strategy model aligns best with continuous delivery where feature branches are merged frequently into a shared integration branch that automatically triggers staging tests?

A.Creating a separate permanent branch for every physical router in the network and never merging them.

B.Locking the master branch for 12 months while developing a single monolithic configuration update offline.

C.Using tag-based releases exclusively without utilizing any version control branches.

D.Trunk-based development where developers merge small, frequent changes into a central main branch that drives automated pipelines.

AnswerD

Correct. Trunk-based development facilitates continuous integration and automated testing.

Why this answer

GitFlow and trunk-based development describe common branching models; trunk-based development or short-lived feature branches with continuous integration are standard for modern DevOps.

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Multi-Selecthard

When executing a configuration commit in Junos via NETCONF, which TWO commit parameters or modifiers can be specified in the RPC? (Choose two)

Select 2 answers

A.Direct packet capture on port 0

B.Check-only validation (verifying syntax without activating the configuration)

C.Confirmed commit (with timeout/rollback functionality)

D.Instant kernel bypass switching

E.Format hard disk partition primary

AnswersB, C

Correct. Check-only validates the config without committing it to production.

Why this answer

NETCONF commit options on Junos include confirmed commits, check-only validation, log messages, etc.

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MCQhard

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?

A.dev.rpc.get_interface_information()

B.dev.get_config(format='xml')

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

D.dev.execute_cli('show interfaces')

AnswerA

PyEZ allows executing RPCs either dynamically via dev.rpc.get_interface_information() or via dev.rpc('get-interface-information').

Why this answer

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.

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MCQeasy

Which Junos automation tool utilizes NETCONF over SSH by default to manage network devices using Python libraries or configuration management frameworks?

A.The local Junos shell (sh) utility

B.Junos PyEZ

C.Wireshark packet analyzer

D.Junos Space Network Management Platform GUI

AnswerB

Correct. Junos PyEZ is a Python library designed for Junos that uses NETCONF over SSH by default.

Why this answer

Ansible, PyEZ, and NETCONF clients communicate with Junos using NETCONF over SSH by default.

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Multi-Selecthard

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)

Select 3 answers

A.ConnectError exception for handling connection failures to the device

B.Config context manager (e.g., 'with Config(dev) as cu:') for handling configuration blocks

C.Docker container orchestration module for spinning up microservices

D.Playbook execution engine for running local bash shell scripts

E.Device class from 'jnpr.junos' for managing connections and sessions

AnswersA, B, E

ConnectError is a standard PyEZ exception raised when a connection cannot be established.

Why this answer

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

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MCQeasy

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?

A.mgd (Management Daemon)

B.jails

C.rpd (Routing Protocol Daemon)

D.jsd (Junos Script Daemon)

AnswerA

mgd processes CLI, NETCONF, and Junos XML/JSON-RPC API requests.

Why this answer

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.

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MCQeasy

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

A.They allow automation scripts to parse device output reliably without relying on brittle regular expressions.

B.Structured data formats take up less memory on the Junos Routing Engine hard drive.

C.They eliminate the need to authenticate when connecting via NETCONF or gRPC.

D.They automatically convert all IPv4 addresses to IPv6 format.

AnswerA

Correct. Structured data eliminates the need for complex, error-prone regex parsing of CLI text.

Why this answer

Structured data formats can be easily parsed programmatically without relying on fragile regular expressions.

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MCQhard

You are configuring a webhook in your version control system to trigger an automated CI/CD pipeline whenever a developer pushes a configuration commit to the main branch of your Junos automation repository. What security mechanism should be implemented on the receiving pipeline webhook endpoint?

A.Validating a shared secret token or HMAC cryptographic signature sent in the webhook request headers.

B.Opening TCP port 22 directly to the public internet without firewall rules.

C.Hardcoding the developer's Linux user password inside the webhook listener script.

D.Disabling all SSL/TLS certificates to allow unencrypted HTTP packet inspection.

AnswerA

Correct. Secret tokens and signatures ensure webhook authenticity.

Why this answer

Webhooks should be secured using secret tokens or HMAC signatures to ensure requests genuinely originate from the trusted VCS platform.

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MCQhard

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?

A.Writing custom Python scripts that use regex to parse 'show route' outputs on the fly.

B.Defining routing policies in Jinja2 templates and YAML data files, committing them to Git, and automatically pushing them via Ansible playbooks.

C.Manually logging into each router via SSH during a maintenance window to type out policy-options statements.

D.Using dynamic routing protocols like BGP to automatically advertise prefixes without human intervention.

AnswerB

Correct. Using templates, data files, version control, and automation tools embodies IaC.

Why this answer

IaC defines infrastructure in declarative configuration files stored in version control, allowing automated testing and deployment.

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Multi-Selecthard

In Git version control, which TWO commands are used to integrate changes from one branch into another? (Choose two)

Select 2 answers

A.git init

B.git merge

C.git status

D.git clone

E.git rebase

AnswersB, E

Correct. git merge joins branch histories together.

Why this answer

Git uses 'merge' and 'rebase' to integrate changes between branches.

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MCQmedium

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?

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

B.junipernetworks.junos.junos_config with 'update: merge' and 'diff: true'

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

D.netconf_config with 'provider: junos'

AnswerB

junos_config with update: merge applies hierarchical configuration blocks and diff: true displays configuration changes.

Why this answer

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.

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