200-901 Practice Test 38 — 15 Questions

Question 1

A Kubernetes Deployment is configured with rolling update strategy. A new version of the image is pushed, and the deployment is updated. During the rollout, the new pods are failing health checks. Which command can be used to pause the rollout and prevent further updates?

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

Accepted Answer

kubectl rollout pause deployment/myapp. The `kubectl rollout pause deployment/myapp` command suspends an in-progress rolling update, preventing Kubernetes from creating additional new ReplicaSets or scaling them further. This is the correct action when new pods are failing health checks, as it halts the rollout without reverting or deleting the deployment, allowing operators to investigate and fix the issue. Once paused, the deployment remains in its current state until resumed with `kubectl rollout resume`.

Answer

kubectl rollout undo deployment/myapp

Answer

kubectl delete deployment/myapp

Answer

kubectl rollout status deployment/myapp

Question 2

Which Cisco platform provides an Intent API for network automation, including endpoints for network-device, topology, and site hierarchy?

Accepted Answer

Cisco Catalyst Center. Cisco Catalyst Center (formerly DNA Center) provides an Intent API that abstracts network intent into RESTful endpoints. This API includes specific endpoints for managing network devices, retrieving topology views, and interacting with site hierarchy, enabling declarative network automation without low-level device configuration.

Answer

Cisco Webex

Answer

Cisco IOS XE

Answer

Meraki Dashboard

Question 3

Which header is used to pass an API key in Meraki Dashboard API requests?

Accepted Answer

X-Cisco-Meraki-API-Key: <key>. Meraki API uses the X-Cisco-Meraki-API-Key header for authentication.

Answer

X-API-Key: <key>

Answer

Authorization: Bearer <token>

Answer

Authorization: Basic <base64>

Question 4

A developer is designing a system that requires high reliability and ordered data delivery. The developer chooses TCP. Which THREE features are provided by TCP?

Accepted Answer

Flow control using window size. TCP provides flow control using a sliding window mechanism (Option A), where the receiver advertises a window size in each segment to prevent the sender from overwhelming its buffer. TCP is connection-oriented (Option D): it establishes a session via the three-way handshake (SYN, SYN-ACK, ACK) before data transfer, which underpins its reliability guarantees. TCP also performs sequencing and retransmission (Option E): each byte is numbered with a sequence number, and unacknowledged segments are retransmitted after a timeout or duplicate ACKs, ensuring ordered, loss-free delivery. Option B is incorrect because multicast is not a TCP feature; TCP is strictly unicast, and multicast delivery is handled by UDP-based or specialized protocols. Option C is incorrect because TCP uses a relatively large 20-byte (minimum) header with many fields, whereas UDP has the simple 8-byte header with minimal overhead.

Answer

Multicast support

Answer

Simple header with minimal overhead

Question 5

An application exposes a REST API. To ensure that only authorized clients can access the API, the developer implements token-based authentication. Which HTTP header is typically used to transmit the bearer token?

Accepted Answer

Authorization: Bearer. The Authorization header with the Bearer scheme (RFC 6750) is the standard method for transmitting bearer tokens in HTTP requests. When a client authenticates and receives a token, it includes the token in the Authorization header as 'Bearer <token>', allowing the server to validate the token and authorize the request without requiring session state.

Answer

Cookie

Answer

X-API-Key

Answer

Authorization: Basic

Question 6

A developer needs to read a JSON configuration file and parse it into a Python dictionary. The file contains nested objects. Which code snippet correctly accomplishes this?

Accepted Answer

with open('config.json', 'r') as f: data = json.load(f). json.load() reads directly from a file object and deserializes the JSON content into a Python dictionary, which is exactly what is needed here. The 'with open(...)' context manager ensures the file is properly closed after reading. This combination handles nested objects natively because json.load() recursively parses the entire JSON structure.

Answer

with open('config.json', 'r') as f: data = json.loads(f)

Answer

data = json.loads(open('config.json', 'r').read())

Answer

with open('config.json', 'r') as f: data = json.dumps(f.read())

Question 7

A company is adopting DevSecOps practices. Which THREE practices should be implemented to secure application deployment?

Accepted Answer

Dependency scanning with tools like Snyk or Dependabot. Option B is correct because dependency scanning with tools like Snyk or Dependabot automatically detects known vulnerabilities (CVEs) in third-party libraries and generates remediation PRs, which is essential for securing the software supply chain in a DevSecOps pipeline. Option C is correct because enforcing HTTPS (via TLS and HSTS) protects data in transit from eavesdropping and man-in-the-middle attacks, while proper CORS configuration restricts which origins can make cross-origin requests, preventing unauthorized data access. Option D is correct because secure coding practices such as input validation and parameterized queries directly mitigate injection flaws (e.g., SQL injection, XSS) at the source, which is a foundational DevSecOps principle of shifting security left. Option A is not appropriate because committing .env files containing secrets to git exposes credentials in version history; secrets should instead be stored in a dedicated secrets manager (e.g., HashiCorp Vault, AWS Secrets Manager). Option E is clearly wrong because disabling security tools increases risk and contradicts the entire purpose of DevSecOps.

Answer

Secrets management using environment variables stored in .env files committed to git

Answer

Disabling all security tools to reduce deployment time

Question 8

A network administrator wants to use EEM on an IOS XE device to send a syslog message whenever a specific CLI command is entered. Which event detector should be used?

Accepted Answer

event cli match. The 'event cli match' detector in EEM triggers when the CLI input on the device matches a specified regular expression pattern. This is exactly what the administrator needs: to detect when a specific CLI command is entered and then take action (send a syslog message). The 'match' keyword uses a regex to compare against the command string typed by the user.

Answer

event syslog pattern

Answer

event interface

Answer

event timer

Question 9

A developer wants to process a list of server hostnames and create a new list containing only hostnames that start with 'web'. Which Python list comprehension correctly accomplishes this?

Accepted Answer

[hostname for hostname in servers if hostname.startswith('web')]. The correct list comprehension is `[hostname for hostname in servers if hostname.startswith('web')]`. It iterates over `servers`, applies the condition `hostname.startswith('web')` as a filter, and includes only those hostnames in the new list. This matches the requirement to create a new list of hostnames starting with 'web'.

Answer

[hostname.startswith('web') for hostname in servers]

Answer

[hostname for hostname in servers if 'web' in hostname]

Answer

[hostname if hostname.startswith('web') for hostname in servers]

Question 10

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 11

A developer needs to update an existing resource via a REST API. The update should be partial, meaning only the fields provided in the request body should be changed. Which HTTP method should be used?

Accepted Answer

PATCH. PATCH is used for partial updates to a resource, while PUT replaces the entire resource.

Answer

DELETE

Answer

PUT

Answer

POST

Question 12

Which THREE of the following are key principles of Infrastructure as Code (IaC) as applied to network automation?

Accepted Answer

Configuration should be idempotent.. Idempotency ensures that applying the same configuration multiple times results in the same final state, preventing unintended changes. In network automation, tools like Ansible or Terraform use idempotent modules (e.g., `ios_config`) to verify the current device state before applying changes, avoiding configuration drift or repeated command failures.

Answer

Manual configuration is preferred for critical devices.

Answer

Temporary scripts should be used for one-time changes.

Question 13

Which HTTP method is used to partially update an existing resource in a RESTful API?

Accepted Answer

PATCH. PATCH is the HTTP method defined for partial modifications to a resource, sending only the fields that need to change. Unlike PUT, which replaces the entire resource representation, PATCH applies a partial update, making it the correct choice for updating a subset of a resource's attributes in a RESTful API.

Answer

UPDATE

Answer

POST

Answer

PUT

Question 14

A developer is designing a Python script that uses the NSO (Network Services Orchestrator) northbound API. Which data format is natively supported by NSO's RESTCONF API?

Accepted Answer

JSON and XML. NSO's RESTCONF API natively supports both JSON and XML data formats, as defined by RFC 8040. RESTCONF uses HTTP methods to manipulate YANG-defined data, and the API can serialize data in either JSON (application/yang-data+json) or XML (application/yang-data+xml) based on the Accept header or Content-Type in the request. This dual-format support allows developers to choose the format that best fits their application's ecosystem.

Answer

YAML only

Answer

JSON only

Answer

XML only

Question 15

A software developer is using the Cisco Webex REST API and wants to filter messages by date range. Which two query parameters should be included? (Choose two.)

Accepted Answer

before. The Cisco Webex REST API uses the 'before' and 'after' query parameters to filter messages by date range. 'before' returns messages sent before a specified date/time, and 'after' returns messages sent after a specified date/time, allowing precise range-based filtering.

Answer

since

Answer

end

Answer

start