200-901 Cisco Platforms and Development — Timed 50 Questions

Question 1

A network engineer needs to automate the configuration of VLANs across 50 switches. Which approach best follows Cisco’s recommended practices for programmability?

Accepted Answer

Write an Ansible playbook using the ios_vlan module to configure VLANs on all switches.. Option A is correct because Ansible's ios_vlan module is purpose-built for automating VLAN configuration on Cisco IOS devices, aligning with Cisco's recommended practices for programmability by using a declarative, agentless automation tool that abstracts the underlying CLI and ensures idempotent configuration across multiple switches.

Answer

Use a REST API on each switch to push the VLAN configuration individually.

Answer

Use a Python script that manually SSHes into each switch and applies CLI commands.

Answer

Configure all VLANs via SNMP MIBs.

Question 2

A developer is building a chatbot that retrieves interface status from a Cisco Catalyst 9000 switch using RESTCONF. Which authentication method is most appropriate for programmatic access?

Accepted Answer

HTTP Basic Authentication over HTTPS.. RESTCONF on Cisco Catalyst 9000 switches supports HTTP Basic Authentication over HTTPS as a straightforward, standards-based method for programmatic access. Basic authentication sends the username and password in the HTTP Authorization header, and when combined with HTTPS, the credentials are encrypted in transit, providing adequate security for device management without requiring additional infrastructure like an OAuth provider or certificate authority.

Answer

API key passed in the HTTP header.

Answer

OAuth 2.0 with client credentials grant.

Answer

Client certificate authentication.

Question 3

During a migration from legacy to SD-Access, a network team wants to use Cisco DNA Center to automate policy deployment. They have defined a macro-level intent but need to ensure that the fabric devices are correctly configured. Which API call should they use to validate the fabric configuration?

Accepted Answer

GET /dna/intent/api/v1/business/sda/fabric-site. The GET /dna/intent/api/v1/business/sda/fabric-site API call retrieves the current configuration of fabric sites, allowing the team to validate that fabric devices are correctly provisioned and associated with the intended site. This aligns with the intent-based API model where GET operations are used for validation and monitoring of deployed policies.

Answer

PUT /dna/intent/api/v1/business/sda/fabric-device

Answer

POST /dna/intent/api/v1/business/sda/fabric-site

Answer

GET /dna/intent/api/v1/business/sda/network-profile

Question 4

A Python script uses the Cisco Meraki API to fetch the list of organizations. The script fails with a 401 HTTP status. What is the most likely cause?

Accepted Answer

The API key is invalid or missing.. A 401 HTTP status indicates 'Unauthorized', which in the context of the Meraki API means the request lacks valid authentication credentials. The most common cause is an invalid or missing API key, as the Meraki API requires a valid API key in the `X-Cisco-Meraki-API-Key` header for all requests.

Answer

The API request exceeded the rate limit.

Answer

The API key does not have permission to list organizations.

Answer

The API endpoint URL is incorrect.

Question 5

A DevOps team is using Cisco NSO to manage network devices. They want to ensure that the configuration is compliant with corporate standards. Which NSO feature should they use?

Accepted Answer

Service reconciliation using FastMap. Service reconciliation using FastMap is the correct NSO feature for ensuring configuration compliance with corporate standards because it detects and corrects deviations between the intended service model (defined in YANG) and the actual device configuration. FastMap performs a diff and re-applies the service logic to bring the device back into compliance, making it ideal for continuous compliance enforcement.

Answer

Configuration Snapshots

Answer

NETCONF notifications

Answer

Configuration Database (CDB) rollback

Question 6

A developer is writing a Python script using the Cisco Webex Teams API to send a message to a specific room. The script works for some rooms but fails for others with a 404 error. What is the most likely reason?

Accepted Answer

The bot is not a member of those rooms.. The 404 error indicates that the resource (the room) was not found by the API. In the Cisco Webex Teams API, a bot can only interact with rooms it has been added to as a member. If the bot is not a member of a room, the API cannot locate the room from the bot's perspective, resulting in a 404 error. This is the most common cause of intermittent 404 errors when the script works for some rooms but not others.

Answer

The API rate limit has been exceeded for those rooms.

Answer

The access token is invalid for those rooms.

Answer

The bot does not have permission to send messages in those rooms.

Question 7

An organization uses Cisco Intersight to manage UCS servers. They want to automate the firmware upgrade process. Which Intersight API should be used to trigger a firmware upgrade on a server?

Accepted Answer

POST /api/v1/compute/Physical. Option D is correct because the `/api/v1/compute/Physical` endpoint in Cisco Intersight is used to manage physical compute resources, including triggering firmware upgrades on UCS servers. By sending a POST request to this endpoint with the appropriate action payload (e.g., `"Action": "UpgradeFirmware"`), you can initiate a firmware upgrade on a specific server. This aligns with Intersight's RESTful API design for lifecycle management of UCS infrastructure.

Answer

POST /api/v1/ntp/Policies

Answer

POST /api/v1/equipment/Fex

Answer

POST /api/v1/fabric/EthNetworkPolicies

Question 8

A network administrator uses the Cisco IOS XE CLI to configure a router. They want to use a Python script to automate this configuration via the guest shell. Which library should they use to interact with the CLI from within the guest shell?

Accepted Answer

cli. The `cli` library is a built-in Python module available within the Cisco Guest Shell that allows scripts to execute IOS XE CLI commands directly on the host device. This library provides functions like `cli.execute()` and `cli.configure()` to send commands and retrieve output, making it the correct choice for automating configuration via the Guest Shell without external dependencies.

Answer

requests

Answer

ncclient

Answer

paramiko

Question 9

Which TWO are benefits of using model-driven programmability (e.g., NETCONF/RESTCONF) over traditional CLI scripting for network automation?

Accepted Answer

Data is structured and machine-readable (e.g., XML/JSON).. Option D is correct because model-driven programmability with NETCONF/RESTCONF uses structured data formats like XML or JSON, which are machine-readable. This eliminates the need for screen-scraping or parsing CLI output, making automation scripts more reliable and easier to maintain. Structured data also enables consistent validation and integration with other systems.

Answer

Reduces network latency because it uses a lighter protocol.

Answer

Requires no additional learning beyond CLI commands.

Answer

Easier to debug because it uses the same syntax as CLI.

Question 10

Which THREE are valid reasons to use Cisco DNA Center's Assurance APIs in an enterprise network?

Accepted Answer

Proactively detect client connectivity issues.. Option B is correct because Cisco DNA Center's Assurance APIs provide proactive monitoring and analytics that can detect client connectivity issues before they impact users, leveraging telemetry data from network devices to identify problems like authentication failures, DHCP timeouts, or signal degradation.

Answer

Automatically enforce QoS policies on switches.

Answer

Collect NetFlow data from all network devices.

Question 11

Which TWO are common authentication methods used when interacting with Cisco APIs?

Accepted Answer

HTTP Basic Authentication. HTTP Basic Authentication (option B) is a common method for authenticating to Cisco APIs, where the client sends a base64-encoded username:password string in the Authorization header. API keys in HTTP headers (option C) are also widely used, especially with REST APIs like Cisco DNA Center or Meraki, where the key is passed in a custom header (e.g., 'X-Cisco-Meraki-API-Key'). Both are simple, stateless mechanisms supported by many Cisco platforms.

Answer

Client certificate exchange

Answer

LDAP bind credentials

Answer

SNMPv3 authentication

Question 12

Refer to the exhibit. A Python script using RESTCONF sends a GET request to retrieve the interface configuration. The response is shown. What is the VLAN assigned to GigabitEthernet1/0/1?

Accepted Answer

10. The correct answer is A (VLAN 10) because the RESTCONF GET response shows the native VLAN for GigabitEthernet1/0/1 is set to 10. In Cisco IOS-XE, the native VLAN is the VLAN assigned to an interface when it is in access mode, and the response explicitly includes the 'native-vlan' field with a value of 10 under the 'Cisco-IOS-XE-native:interface' hierarchy.

Answer

1

Answer

100

Answer

20

Question 13

Refer to the exhibit. A service engineer runs a 'check-sync' action on the NSO service 'vpn1'. The result shows 'out-of-sync' for device 'pe1'. What does this indicate?

Accepted Answer

The configuration on pe1 differs from the service model defined in NSO.. The 'check-sync' action in NSO compares the actual device configuration (retrieved via NETCONF or CLI) against the configuration that NSO's service model expects. An 'out-of-sync' result for device 'pe1' means the running configuration on pe1 does not match the configuration defined by the NSO service model for that device. This is a standard NSO feature to detect configuration drift.

Answer

The device pe1 is unreachable via NETCONF.

Answer

The service model in NSO does not have a configuration for pe1.

Answer

The device pe1 has a hardware failure.

Question 14

A large enterprise operates a multi-vendor network with Cisco routers and switches, as well as Juniper devices. The network team uses Ansible for automation, with a centralized control node running RHEL. They have been using the 'ios_config' module for Cisco devices and 'junos_config' for Juniper devices. Recently, they added a new Cisco Catalyst 9300 switch to the network. They wrote a playbook to configure VLAN 100 on the switch, but the task fails with the error: 'module_stderr: Could not find platform module for Cisco IOS XE'. The playbook uses the 'cisco.ios.ios_config' module. The control node has the 'cisco.ios' collection installed (version 2.0.0). The target switch runs IOS XE 16.12.3. The control node can SSH to the switch successfully. Which action will most likely resolve the issue?

Accepted Answer

Upgrade the 'cisco.ios' Ansible collection to the latest version.. The error 'Could not find platform module for Cisco IOS XE' indicates that the installed 'cisco.ios' collection (version 2.0.0) does not include a module or plugin that supports the IOS XE platform for the target switch. Upgrading the collection to the latest version ensures compatibility with IOS XE 16.12.3, as newer releases add support for newer platforms and OS versions.

Answer

Configure the switch to allow SSH connections from the control node IP.

Answer

Use the 'raw' module instead of 'ios_config' to send CLI commands directly.

Answer

Install Python 3.8 on the control node and update the ansible.cfg to use it.

Question 15

A university IT department manages a Cisco Meraki network with 200 MR access points and 50 MS switches. They use the Meraki dashboard API to automate network provisioning. A new student dormitory was added, and the team needs to create a new network and claim devices. They have a Python script that uses the Meraki API to create the network and then claim devices by serial numbers. The script successfully creates the network but fails when claiming devices with a 400 error: 'Device serial number is not valid or already claimed'. The serial numbers are correct and unused. The API key has full organization access. The script uses the endpoint 'POST /networks/{networkId}/devices/claim' with the correct body. What is the most likely cause of the failure?

Accepted Answer

The devices have not been added to the organization's inventory first.. Option C is correct because in the Meraki API workflow, devices must first be added to the organization's inventory via the 'POST /organizations/{organizationId}/inventory/devices' endpoint before they can be claimed into a specific network. The 400 error 'Device serial number is not valid or already claimed' occurs when the serial numbers are not present in the organization's inventory, even if they are correct and unused. The script successfully creates the network but fails at the claim step because the devices have not been inventoried at the organization level.

Answer

The API key does not have permission to claim devices.

Answer

The serial numbers contain a typo.

Answer

The devices are not Meraki MR or MS models.

Question 16

A developer is automating VLAN configuration on a Cisco switch using REST API. Which HTTP method should be used to create a new VLAN?

Accepted Answer

POST. To create a new VLAN resource on a Cisco switch via REST API, the POST method is correct because it is designed to create a subordinate resource under a parent collection. In RESTful APIs, POST is used to send data to the server to create a new entity, such as a VLAN, and the server assigns a unique identifier (e.g., VLAN ID) to the new resource. This aligns with the RESTful principle for resource creation, as specified in RFC 7231.

Answer

PUT

Answer

GET

Answer

PATCH

Answer

DELETE

Question 17

Which TWO of the following are characteristics of Model-Driven Programmability with YANG models?

Accepted Answer

YANG models define a hierarchical data tree.. Option A is correct because YANG models define a hierarchical data tree structure that organizes configuration and state data in a parent-child relationship, mirroring the structure of the device's operational and configuration data. This hierarchical representation allows for precise, path-based access to individual data nodes, which is fundamental to model-driven programmability.

Answer

YANG models are only used with the Python library ncclient.

Answer

The controller directly pushes configurations to network devices without validation.

Answer

NETCONF requires JSON encoding for configuration data.

Question 18

Refer to the exhibit. A developer sends a PUT request to the RESTCONF endpoint with the above JSON payload. The device already has interface GigabitEthernet1/0/1 configured with IP address 10.10.10.1/24. What is the expected outcome?

Accepted Answer

The request succeeds and the interface configuration remains unchanged.. D is correct because the PUT request to the RESTCONF endpoint with the provided JSON payload is an idempotent operation. Since the interface GigabitEthernet1/0/1 already exists with the exact same configuration (IP address 10.10.10.1/24), the PUT request effectively replaces the resource with the same data, resulting in no change. RESTCONF uses the HTTP PUT method to create or replace a resource, and if the resource already exists and the payload matches, the operation succeeds without modification.

Answer

The request fails because the interface already exists.

Answer

The request creates a new interface with the same configuration.

Answer

The request fails because the JSON is malformed.

Question 19

Drag and drop the steps to configure a new VLAN on a Cisco switch into the correct order.

Question 20

Drag and drop the steps to use Git to commit and push code changes to a remote repository into the correct order.