200-901 Practice Test 46 — 15 Questions

Question 1

An engineer is troubleshooting a Cisco DNA Center API call that returns a 401 error. What is the most likely cause?

Accepted Answer

The authentication token has expired. A 401 Unauthorized error from the Cisco DNA Center API indicates that the request lacks valid authentication credentials. The most common cause is that the authentication token (JWT) obtained via the /dna/system/api/v1/auth/token endpoint has expired. Cisco DNA Center tokens have a default expiry of 60 minutes, after which the API rejects the request with a 401 status.

Answer

The network device is unreachable

Answer

The request body is invalid

Answer

The API endpoint is incorrect

Question 2

A Kubernetes deployment is configured with replicas: 3. During a rolling update, the deployment strategy is set to RollingUpdate with maxSurge: 1 and maxUnavailable: 0. What is the maximum number of pods that will be running during the update?

Accepted Answer

4. With maxSurge=1, one extra pod can be created above the desired 3, and maxUnavailable=0 ensures no pods are taken down before new ones are ready. So the maximum is 4 pods.

Answer

6

Answer

5

Answer

3

Question 3

Refer to the exhibit. During a rolling update, a developer notices that the new pods are not passing the readiness probe and the update stalls. What is the most likely reason?

Accepted Answer

The readiness probe path /health is not implemented in the new image.. The rolling update stalls because the new pods fail the readiness probe. The readiness probe is configured to check the /health endpoint, and if that endpoint is not implemented in the new image, the probe never returns a success status. Kubernetes will not route traffic to pods that fail the readiness probe, and the rolling update will not proceed to replace old pods until the new ones are ready.

Answer

The rolling update strategy is configured incorrectly with maxUnavailable and maxSurge.

Answer

The image tag is incorrect.

Answer

The selector does not match the new pods' labels.

Question 4

Which THREE of the following are common tools used in a CI/CD pipeline for network automation? (Choose three.)

Accepted Answer

Jenkins. Jenkins is a widely used automation server that orchestrates CI/CD pipelines, including those for network automation, by triggering jobs such as configuration validation or deployment upon code commits. Its plugin ecosystem integrates with network tools like Ansible and Git, making it a core component for automating network changes.

Answer

VMware vSphere

Answer

Docker

Question 5

In the context of REST API design, which HTTP status code should be returned when a client sends a request that exceeds the API rate limit?

Accepted Answer

429 Too Many Requests. (429 Too Many Requests) is correct because RFC 6585 defines this status code specifically for cases where a client has sent too many requests in a given time frame, exceeding the API's rate limit. REST APIs use this response to enforce throttling and inform the client to back off, often including a Retry-After header to indicate when to retry.

Answer

503 Service Unavailable

Answer

400 Bad Request

Answer

401 Unauthorized

Question 6

A developer is writing a Python script to interact with a Cisco device using NETCONF. Which library is most appropriate?

Accepted Answer

ncclient. The most appropriate library for NETCONF operations in Python is ncclient (option D). ncclient is a Python library that provides a client for NETCONF, allowing interaction with network devices via NETCONF protocol. Option A (netmiko) is used for SSH/Telnet connections to network devices but does not natively support NETCONF. Option B (requests) is for HTTP requests, not NETCONF. Option C (paramiko) is a pure Python SSH implementation, which is not suitable for NETCONF. Therefore, ncclient is the correct choice.

Answer

netmiko

Answer

requests

Answer

paramiko

Question 7

Which TWO of the following are valid reasons to use a trunk link between two switches? (Select exactly two.)

Accepted Answer

To interconnect switches in a multi-VLAN environment.. Trunk links are specifically designed to interconnect switches in a multi-VLAN environment, allowing the switches to exchange frames tagged with VLAN information using the 802.1Q protocol. Without a trunk, each VLAN would require a separate physical link between switches, which is inefficient and does not scale.

Answer

To connect a switch to a router using a single link for one VLAN.

Answer

To increase bandwidth between switches by combining multiple links.

Answer

To reduce latency by using 802.1Q encapsulation.

Question 8

An engineer needs to troubleshoot a RESTCONF request that returns a 409 Conflict error when trying to modify a YANG data node. What is the most likely cause?

Accepted Answer

The resource was modified by another client during the operation. A 409 Conflict error in RESTCONF specifically indicates a resource state conflict, typically caused by a YANG data store version mismatch detected via the 'if-match' header or ETag validation. When another client modifies the same resource between the time a client retrieves it and attempts to update it, the server rejects the request to prevent lost updates, enforcing optimistic locking as defined in RFC 8040.

Answer

The data node is read-only

Answer

Authentication failure

Answer

The YANG model version mismatch

Question 9

Which THREE steps are essential in a typical CI/CD pipeline for a containerized application? (Choose THREE.)

Accepted Answer

Build the Docker image. Building the Docker image is essential because it packages the application code, dependencies, and runtime into a portable container. Without this step, there is no deployable artifact for the CI/CD pipeline to promote through stages.

Answer

Perform code review

Answer

Deploy directly to production without testing

Question 10

A Python function is designed to fetch device data from multiple sources. It uses *args to accept variable number of API endpoints and **kwargs for optional parameters like timeout. Which function definition correctly implements this?

Accepted Answer

def fetch_devices(*endpoints, **options):. It uses *endpoints to accept a variable number of positional arguments (the API endpoint strings) and **options to accept any number of keyword arguments (like timeout=30). This matches the requirement for a function that can handle multiple sources with optional parameters, following Python's standard *args/**kwargs pattern.

Answer

def fetch_devices(**endpoints, *options):

Answer

def fetch_devices(endpoints, **options):

Answer

def fetch_devices(*endpoints, options):

Question 11

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

Accepted Answer

192.168.0.0/16. RFC 1918 reserves the 192.168.0.0/16 block (192.168.0.0 – 192.168.255.255) as a private IPv4 address range, meaning these addresses are not routable on the public internet and are intended for use within private networks.

Answer

169.254.0.0/16

Answer

11.0.0.0/8

Answer

172.32.0.0/12

Question 12

A network technician runs the command 'ping 8.8.8.8' from a workstation and receives 'Reply from 192.168.1.1: Destination host unreachable.' What does this indicate?

Accepted Answer

There is a routing issue beyond the local network.. The 'Reply from 192.168.1.1: Destination host unreachable' message indicates that the local router (192.168.1.1) received the ICMP echo request for 8.8.8.8 but could not find a route to that destination in its routing table. This means the router has a valid path back to the workstation (so the default gateway is reachable), but it lacks a route to the remote network, pointing to a routing issue beyond the local subnet.

Answer

DNS resolution is failing.

Answer

The default gateway is misconfigured.

Answer

The workstation has no internet connectivity.

Answer

The remote server is down.

Question 13

A team is deploying a microservice that must scale independently. The service uses environment variables for configuration. Which Kubernetes resource should be used to store non-sensitive configuration data separate from the container image?

Accepted Answer

ConfigMap. ConfigMap is the correct Kubernetes resource for storing non-sensitive configuration data (like environment variables) separately from the container image. This allows the microservice to scale independently because configuration changes can be applied without rebuilding or redeploying the image, enabling stateless, horizontally scalable pods.

Answer

Secret

Answer

Service

Answer

Deployment

Question 14

During a security audit, an engineer discovers that a CI/CD pipeline is storing API keys in plain text in environment variables. Which best practice should be implemented to mitigate this risk?

Accepted Answer

Use a dedicated secrets management service like HashiCorp Vault or AWS Secrets Manager and retrieve secrets at runtime.. Dedicated secrets management services like HashiCorp Vault or AWS Secrets Manager provide secure storage, access control, and audit logging for sensitive data. They allow the CI/CD pipeline to retrieve API keys at runtime via authenticated API calls, ensuring secrets are never stored in plain text in environment variables or configuration files. This approach aligns with the principle of least privilege and eliminates the risk of exposure through source code or build logs.

Answer

Store secrets in a .env file and add it to the repository with restricted access.

Answer

Encrypt the environment variables using a tool like openssl and store the key elsewhere.

Answer

Remove the API keys from the pipeline and require manual entry each time a build runs.

Question 15

A developer needs to create a Postman collection that uses a variable for the base URL and a token variable for authentication. The token is obtained from a login request and must be reused across requests. Where should the token variable be defined to persist across all requests in the collection?

Accepted Answer

As a collection variable. Collection variables in Postman are scoped to the entire collection, meaning they persist across all requests within that collection. By storing the token as a collection variable after the login request, it can be reused in subsequent requests without re-authentication. This is the recommended approach for sharing authentication tokens across requests in a Postman collection.

Answer

As a data variable from a CSV file

Answer

As a global variable

Answer

As a local variable in the login request