200-901 Infrastructure and Automation Practice Test 3 — 15 Questions

Question 1

A DevOps team uses Ansible to configure Cisco Nexus switches for a new data center. They have a playbook that uses the nxos_vlan module to create VLANs and nxos_interface module to assign access VLANs. The playbook runs successfully on the first Nexus switch but fails on the second with error: 'module_stderr: ntclib: error: unable to connect to switch'. Both switches are reachable via ping and SSH from the Ansible control node. The inventory file has the same SSH credentials for both switches. What is the most likely cause of the connection failure on the second switch?

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

Accepted Answer

The second switch does not have NX-API enabled.. The error 'module_stderr: ntclib: error: unable to connect to switch' indicates that the Ansible nxos modules are attempting to use NX-API (REST-like HTTP/HTTPS API) to communicate with the switch, not SSH. Even though SSH is reachable, the second switch likely has NX-API disabled or not configured, causing the connection failure. The nxos_vlan and nxos_interface modules in Ansible rely on NX-API by default when the connection type is set to 'network_cli' or 'httpapi', and without NX-API enabled, the modules cannot execute.

Answer

The Ansible control node has an incompatible version of the nxos collection.

Answer

The second switch has a different VLAN database that conflicts with the playbook.

Answer

The second switch's SSH key fingerprint has changed and is not accepted.

Question 2

Which TWO of the following are commonly used protocols for network automation?

Accepted Answer

RESTCONF. RESTCONF (A) is correct because it is a standardized IETF protocol (RFC 8040) that provides a RESTful, HTTP-based interface using YANG-modeled data to programmatically configure and retrieve device state for network automation. NETCONF (B) is correct because it is an IETF protocol (RFC 6241) that uses XML-encoded RPCs over SSH to install, manipulate, and delete configuration on network devices, making it a foundational automation protocol. HTTP (C) is not a network-automation protocol itself; it is a generic transport used by RESTCONF and other APIs. SNMP (D) is primarily a monitoring and management protocol for polling and traps, not a modern model-driven configuration automation protocol. SSH (E) is a secure transport protocol commonly used to carry NETCONF and CLI sessions, but it is not itself a network automation protocol.

Answer

HTTP

Answer

SNMP

Answer

SSH

Question 3

A developer is writing a Python script that uses the Cisco Meraki Dashboard API to update the name of a specific network. The script must authenticate using an API key and send the updated name in the request body. Which HTTP method and request header should the script use to perform this update?

Accepted Answer

PUT with header 'X-Cisco-Meraki-API-Key: <key>'. To update a network's name via the Meraki Dashboard API, the correct HTTP method is PUT, and authentication requires the 'X-Cisco-Meraki-API-Key' header. The API key must be included in the request header, and the new name is sent in the JSON body. This ensures the network resource is updated as intended.

Answer

POST with header 'Authorization: Bearer <key>'

Answer

PATCH with header 'X-Cisco-Meraki-API-Key: <key>'

Answer

GET with header 'X-Cisco-Meraki-API-Key: <key>'

Question 4

A network engineer is building a Python script that consumes a REST API on a Cisco IOS XE device using the RESTCONF protocol. The device returns a response with Content-Type: application/yang-data+json. Which Python code correctly parses the response body into a dictionary?

Accepted Answer

data = response.json(). The .json() method of a requests Response object automatically deserializes a JSON body into Python native types. Since the Content-Type header indicates JSON, calling response.json() yields a dictionary that the script can immediately use. The other options either return raw bytes or strings, or use an alternative parsing path that is less idiomatic.

Answer

data = response.text

Answer

data = json.loads(response.text)

Answer

data = response.content

Question 5

A network automation engineer is using Ansible to configure a Cisco IOS XE device. The playbook uses the 'ios_config' module to push a banner. After running the playbook, the engineer notices that the banner was not applied, but the playbook reported no errors. Which Ansible directive should the engineer add to the task to ensure that the configuration change is saved to the startup configuration?

Accepted Answer

In the ios_config task, add the parameter 'save_when: always'. The 'ios_config' module includes a 'save_when' parameter that controls saving the running configuration to the startup configuration. By default, it does not save. Setting 'save_when: always' ensures the configuration is saved after each run, making the banner persistent. This is the correct way to ensure changes are saved without relying on handlers or separate tasks.

Answer

ios_config: save_when=always

Answer

notify: save config

Answer

save_when: modified

Question 6

A developer is building a Python tool that consumes the Cisco Meraki Dashboard API. The organization has thousands of networks, and the tool must page through the full list of networks for an organization without missing entries. Which technique correctly handles pagination in the Meraki API?

Accepted Answer

Read the Link HTTP response header and follow the rel="next" URL until no next link is returned.. The Meraki Dashboard API signals more results through HTTP Link headers containing a rel="next" URL. A correct client parses that header and keeps requesting the next URL until it is absent. Fixed page counters, non-existent cursor parameters, and oversized perPage values all fail to traverse the full dataset, making header-driven pagination the reliable technique.

Answer

Use the startingAfter query parameter with the last object's ID until the response is empty.

Answer

Set the perPage query parameter to a value larger than the total network count and make a single request.

Answer

Increment the page query parameter starting at 1 until an empty JSON array is returned.

Question 7

A network automation engineer is using the Cisco Meraki Dashboard API to update the configuration of a specific switch port. The engineer needs to change the port's VLAN assignment. Which HTTP method and endpoint should be used to accomplish this task?

Accepted Answer

PUT /devices/{serial}/switch/ports/{portId}. To update a switch port's VLAN assignment via the Meraki Dashboard API, the correct operation is an HTTP PUT to the device-specific endpoint that includes the switch serial and port identifier. This method replaces the port's configuration with the provided values. The other options use incorrect HTTP methods or endpoint structures that do not match the API's design for updating switch ports.

Answer

GET /devices/{serial}/switch/ports/{portId}

Answer

POST /devices/{serial}/switch/ports

Answer

PATCH /networks/{networkId}/switch/ports/{portId}

Question 8

A network automation engineer is using the Cisco IOS XE RESTCONF API to retrieve the running configuration of a router. The engineer sends a GET request to the RESTCONF endpoint with the Accept header set to application/yang-data+json. The router returns a 200 OK response but the body is empty. Which action should the engineer take to retrieve the configuration data?

Accepted Answer

Add the query parameter ?depth=unbounded to the request URL.. When using RESTCONF to retrieve configuration data, the depth query parameter controls how many levels of the data tree are returned. Without it, a GET to a top-level container like Cisco-IOS-XE-native:native may return an empty or shallow response. Setting depth=unbounded ensures the entire subtree is included. This is a common pitfall when working with YANG models that have deep hierarchies, and it explains why a 200 OK with an empty body can occur.

Answer

Send a POST request to the same endpoint with a body specifying the desired configuration.

Answer

Verify the resource path and include the correct YANG model path for the running configuration, such as /restconf/data/Cisco-IOS-XE-native:native.

Answer

Change the Accept header to application/yang-data+xml.

Question 9

A network automation team stores device inventory in a plain-text file that Ansible reads at runtime. The file lists routers, switches, and their management IP addresses under host groups, and the team wants to add per-device variables such as `ansible_network_os`. Which Ansible inventory format should be used so the inventory remains human-readable and supports grouping and host variables natively?

Accepted Answer

An INI-style inventory file. Ansible inventories can be written in INI or YAML, and both support groups and per-host variables. The INI format uses bracketed group names, the :children suffix for nested groups, and key=value pairs for variables, keeping the file compact and easy to edit by hand. Other file types mentioned serve unrelated purposes such as certificates, data modeling, or API description and are not parsed as inventories.

Answer

A YANG model file

Answer

An OpenAPI specification document

Answer

A PEM-encoded certificate bundle

Question 10

A developer is building a Python application that interacts with a REST API. The API requires authentication via an API key, which must be included in the request header. The developer wants to write a function that sends a GET request to the API endpoint and returns the JSON response. Which code snippet correctly implements this using the requests library?

Accepted Answer

import requests

def get_data(url, api_key):
    headers = {'Authorization': f'Bearer {api_key}'}
    response = requests.get(url, headers=headers)
    response.raise_for_status()
    return response.json(). The correct implementation uses the requests library to send a GET request with the API key in the Authorization header as a Bearer token, and includes raise_for_status() to handle HTTP errors. This matches the API's authentication requirement and ensures robust error handling. The other options either misuse the auth parameter, send the key insecurely as a query parameter, or use an incorrect header name, and most lack proper error handling.

Answer

import requests

def get_data(url, api_key):
    response = requests.get(url, params={'api_key': api_key})
    return response.json()

Answer

import requests

def get_data(url, api_key):
    response = requests.get(url, auth=api_key)
    return response.json()

Answer

import requests

def get_data(url, api_key):
    response = requests.get(url, headers={'api_key': api_key})
    return response.json()

Question 11

A developer is writing a Python script that uses the Meraki Dashboard API to update the VLAN configuration on a specific switch port. The script must first retrieve the current configuration, modify the VLAN assignment, and then apply the change. Which sequence of HTTP methods and API endpoints should the developer use?

Accepted Answer

GET /devices/{serial}/switch/ports, then PUT /devices/{serial}/switch/ports/{portId}. To update a switch port's VLAN via the Meraki Dashboard API, the developer must first retrieve the current port configuration using a GET request. Then, a PUT request to the specific port endpoint applies the changes. The Meraki API uses PUT for updates and does not support PATCH for this resource. The correct sequence ensures the developer has the necessary context and uses the appropriate HTTP method.

Answer

PATCH /devices/{serial}/switch/ports/{portId}, then GET /devices/{serial}/switch/ports

Answer

PUT /devices/{serial}/switch/ports/{portId}, then GET /devices/{serial}/switch/ports

Answer

GET /devices/{serial}/switch/ports, then POST /devices/{serial}/switch/ports/{portId}

Question 12

A developer needs to configure a Cisco IOS XE router using NETCONF. The developer wants to send a configuration change and ensure the device applies it only if the candidate datastore matches the running configuration, otherwise the operation should fail and leave the device unchanged. Which NETCONF capability must be advertised by the device for this atomic, all-or-nothing behavior?

Accepted Answer

urn:ietf:params:netconf:capability:candidate:1.0. The candidate datastore lets a client stage configuration edits, validate them, and commit them as one transaction. If validation fails, nothing is applied to running. Writable-running applies edits immediately, rollback-on-error only reverts failed transactions, and notifications carry event data rather than configuration state. For atomic, all-or-nothing changes that must match the running configuration, the candidate capability is required.

Answer

urn:ietf:params:netconf:capability:notification:1.0

Answer

urn:ietf:params:netconf:capability:writable-running:1.0

Answer

urn:ietf:params:netconf:capability:rollback-on-error:1.0

Question 13

An engineer needs to automate the deployment of a new VLAN across multiple switches. Which tool is best suited for this task?

Accepted Answer

Ansible. Ansible is the correct tool because it is an agentless automation platform that uses SSH to push configuration changes, such as VLAN deployment, to network devices. It allows engineers to define the desired state of VLANs in YAML playbooks and apply them consistently across multiple switches without manual intervention.

Answer

NetFlow

Answer

Syslog

Answer

SNMP

Question 14

A DevOps team wants to version control their network configurations. Which tool should they use?

Accepted Answer

Git. Git is a distributed version control system that tracks changes in source code and configuration files, making it the ideal tool for version controlling network configurations. Unlike configuration management tools, Git provides commit history, branching, and rollback capabilities specifically designed for version control.

Answer

Puppet

Answer

Jenkins

Answer

Docker

Question 15

During an automation script run, a network device returns HTTP 429. What does this indicate?

Accepted Answer

Rate limiting. HTTP 429 (Too Many Requests) indicates the client has sent too many requests in a given amount of time, triggering rate limiting on the server. In network automation, devices like routers or switches enforce rate limits to prevent resource exhaustion, often based on RFC 6585. This is common when automation scripts exceed API call thresholds, requiring retry logic with exponential backoff.

Answer

Internal server error

Answer

Authentication failure

Answer

Resource not found