200-901 Practice Test 27 — 15 Questions

Question 1

A CI/CD pipeline for a Python project should run unit tests and check for known vulnerabilities in dependencies. Which tool can be integrated into the pipeline to perform dependency scanning?

Accepted Answer

Snyk. Snyk is a popular dependency scanning tool that integrates with CI/CD pipelines. pip audit and npm audit are similar but for specific ecosystems. Snyk supports multiple languages.

Answer

Docker

Answer

Kubernetes

Answer

Jenkins

Question 2

A developer is writing a Python script to iterate over a list of server hostnames. Which loop structure is most appropriate to process each hostname in the list?

Accepted Answer

for hostname in hostnames: print(hostname). The 'for item in list' loop iterates directly over each element, making it the simplest and most readable for processing each hostname.

Answer

for i, hostname in enumerate(hostnames): print(hostname)

Answer

while len(hostnames) > 0: print(hostnames.pop())

Answer

for i in range(len(hostnames)): print(hostnames[i])

Question 3

A developer needs to retrieve the hostname of a Cisco IOS XE device using RESTCONF. Which URI path is correct?

Accepted Answer

/restconf/data/Cisco-IOS-XE-native:native/hostname. RESTCONF uses the YANG module namespace. The native hostname is at /restconf/data/Cisco-IOS-XE-native:native/hostname.

Answer

/restconf/data/Cisco-IOS-XE-native:hostname

Answer

/api/v1/device/hostname

Answer

/restconf/data/hostname

Question 4

Which THREE are benefits of using YANG as a data modeling language for network automation? (Select exactly 3.)

Accepted Answer

Enables validation of data constraints before applying changes. YANG (RFC 6020/7950) allows you to define data constraints such as ranges, mandatory elements, and type restrictions directly in the model. When you attempt to apply configuration via NETCONF or RESTCONF, the server validates the data against these constraints before committing, preventing invalid changes from being applied.

Answer

Allows direct execution of CLI commands on any device

Answer

Supports multiple serialization formats like JSON and XML

Question 5

Which TWO statements about REST API design best practices are true? (Choose two.)

Accepted Answer

Use nouns for resource endpoints, e.g., /devices instead of /getDevices. Option D is correct because REST best practice is to model endpoints as resources using nouns (e.g., /devices), letting the HTTP method express the action rather than embedding verbs in the URI. Option E is correct because REST relies on standard HTTP methods with their defined semantics: GET for safe retrieval, POST for creating resources, PUT/PATCH for updates, and DELETE for removal, which keeps the interface uniform and predictable. Options A, B, and C are not correct: versioning is generally recommended (e.g., /v1/devices or a version header) to allow evolution without breaking clients, so avoiding it is poor practice; putting the method in the path like /getDevices violates the noun-based resource convention and duplicates HTTP semantics; and file-based transfer is not a REST design rule—large payloads are typically handled with streaming, pagination, or chunked transfer rather than mandating file-based transfer.

Answer

Avoid API versioning to keep the API simple

Answer

Include the HTTP method in the URI path, e.g., /getDevices

Answer

Always use file-based transfer for large payloads

Question 6

Which TWO of the following are commonly used when implementing pagination in REST APIs? (Select TWO)

Accepted Answer

Cursor-based token in response. Option A (cursor-based token in response) is correct because cursor pagination returns an opaque token (often in a 'next_cursor' or Link header) that the client sends back to fetch the next page, giving stable results even when records are inserted or deleted. Option D (offset and limit query parameters) is correct because it is the most common pagination pattern, e.g. GET /items?offset=20&limit=10, where limit caps page size and offset skips records. Option B (rate limiting headers) is wrong because headers like X-RateLimit-Remaining or Retry-After govern request throttling, not page navigation. Option C (OAuth 2.0 token) is wrong because it is an authorization credential (bearer token), unrelated to paginating result sets. Option E (webhook callback URL) is wrong because webhooks push event notifications to a subscriber endpoint, not retrieve successive pages of a collection.

Answer

Rate limiting headers

Answer

OAuth 2.0 token

Answer

Webhook callback URL

Question 7

Which of the following is a private IPv4 address range as defined by RFC 1918?

Accepted Answer

10.0.0.0/8. The private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. 169.254.0.0/16 is link-local (APIPA).

Answer

192.167.0.0/16

Answer

169.254.0.0/16

Answer

172.32.0.0/12

Question 8

Which TWO methods are commonly used to discover network devices in an automation environment? (Select exactly 2.)

Accepted Answer

Using LLDP or CDP to retrieve directly connected neighbor information. LLDP (IEEE 802.1AB) and CDP (Cisco Discovery Protocol) are Layer 2 protocols that allow network devices to advertise their identity, capabilities, and directly connected neighbors. In automation environments, these protocols enable dynamic discovery of the network topology without manual intervention, making them essential for automated inventory and mapping.

Answer

Manually entering device details into a spreadsheet

Answer

Using SNMP to bulk-configure devices

Answer

Monitoring DHCP logs to lease IP addresses to new devices

Question 9

Which TWO statements about REST API design best practices are correct?

Accepted Answer

Resources should be represented using nouns in the URI. Option C is correct because REST best practice dictates that URIs identify resources, not actions, so they should use nouns (e.g., /users/123) rather than verbs like /getUser. Option E is correct because in REST the HTTP method itself conveys the action on the resource — GET retrieves, POST creates, PUT replaces, PATCH partially updates, and DELETE removes — keeping the URI action-free. Option A is wrong because versioning is commonly done via URI path (e.g., /v1/users), custom media types, or headers, not query parameters only. Option B is wrong because PUT is meant for full resource replacement, while PATCH is the correct method for partial updates. Option D is wrong because REST responses typically include a representation (JSON/XML) in the body along with the status code, not just a bare status code.

Answer

API versioning should be implemented using query parameters only

Answer

HTTP PUT method should be used for partial updates to a resource

Answer

Responses should return only HTTP status codes without a body

Question 10

A team is using Python scripts with netmiko to back up configurations from a large number of network devices. What is the primary advantage of using netmiko over direct paramiko for this task?

Accepted Answer

Netmiko simplifies the handling of device-specific prompts and command output. Netmiko is built on top of Paramiko but adds a higher-level abstraction layer that automatically handles device-specific prompt detection, command output parsing, and SSH session management. This simplifies the backup process across heterogeneous devices by eliminating the need to manually write code for each device's unique prompt patterns and command responses.

Answer

Netmiko supports only Cisco devices

Answer

Netmiko uses REST API instead of SSH

Answer

Netmiko is faster than paramiko

Question 11

A team is building a CI/CD pipeline for network automation. They want to use Cisco Modeling Labs (CML) to validate configuration changes before production. What is the best approach to integrate CML into the pipeline?

Accepted Answer

Use CML's REST API to start a simulation, apply changes, run tests, then tear down. D is correct because CML provides a REST API that allows programmatic lifecycle management of simulations. Integrating this API into a CI/CD pipeline enables the pipeline to dynamically create an isolated test environment, apply configuration changes, run validation tests, and then tear down the simulation to free resources. This approach ensures repeatability, isolation, and efficient resource usage, which are critical for automated network validation.

Answer

Use the pyATS framework to connect to CML and run tests

Answer

Create a permanent topology in CML for each branch

Answer

Use Ansible to provision CML nodes directly

Question 12

A developer is creating a Python script to retrieve interface statistics from a Cisco IOS XE device using RESTCONF. Which HTTP method should be used to get the data?

Accepted Answer

GET. RESTCONF uses standard HTTP methods to perform CRUD operations on YANG-defined data. To retrieve interface statistics without modifying any resource, the GET method is correct, as it maps directly to the NETCONF or operation for reading data.

Answer

POST

Answer

PUT

Answer

DELETE

Question 13

Refer to the exhibit. A developer receives this response from Cisco DNA Center API. What is the most likely cause and solution?

Accepted Answer

The token is expired; generate a new one using /dna/system/api/v1/auth/token.. The HTTP 401 Unauthorized response indicates that the request lacks valid authentication credentials. In Cisco DNA Center API, tokens are short-lived (default 1 hour) and must be refreshed via POST /dna/system/api/v1/auth/token. The error is not about the endpoint, body syntax, or RBAC permissions — it specifically means the token used is expired or invalid.

Answer

The API path is incorrect; verify the endpoint URL.

Answer

The request body is malformed; check JSON syntax.

Answer

The user does not have permission; request admin to grant access.

Question 14

A DevOps team manages network infrastructure using Infrastructure as Code (IaC). They store configuration files in a Git repository and use CI/CD to deploy changes. What is the best practice to ensure that only validated configurations are applied to production devices?

Accepted Answer

Require a pull request with at least one approval before merging to the main branch. Requiring a pull request with at least one approval before merging to the main branch enforces peer review and validation of configuration changes. This ensures that only code that has been reviewed for correctness, syntax, and adherence to standards is merged, preventing erroneous or malicious configurations from reaching production via the CI/CD pipeline.

Answer

Allow any team member to push directly to the main branch after testing locally

Answer

Use a manual approval gate in the CI/CD pipeline that requires manager sign-off

Answer

Automate the deployment of every commit directly to production

Question 15

An organization wants to automate the deployment of wireless configurations across multiple Meraki networks using the Meraki Dashboard API. What authentication method should the developer use in the API requests?

Accepted Answer

Include an API key in the X-Cisco-Meraki-API-Key header. The Meraki Dashboard API uses a simple API key for authentication, not OAuth2 or JWT. The key must be included in the `X-Cisco-Meraki-API-Key` header of every request. This is the only supported method for authenticating with the Meraki API, as documented by Cisco Meraki.

Answer

Provide username and password in the Authorization header with Basic auth

Answer

Use OAuth2 client credentials grant and pass a bearer token

Answer

Generate a JSON Web Token (JWT) signed with a shared secret