200-901 Practice Test 4 — 25 Questions

Question 1

Which header is used in an HTTP request to tell the server the format of the request body?

Accepted Answer

Content-Type. Content-Type header specifies the media type of the request body, e.g., application/json.

Answer

Authorization

Answer

Accept

Answer

Host

Question 2

A company has a three-tier data center architecture with access, aggregation, and core layers. The network team is migrating to a leaf-spine architecture to support increasing east-west traffic. The current network uses STP for loop prevention, and the team wants to eliminate STP in the new design. They plan to use VXLAN overlays with BGP EVPN for control plane. During a pilot deployment, the team notices that some legacy servers that rely on traditional VLANs are not reachable across the new fabric. The servers are connected to access switches that are part of the leaf layer. The access switches are configured as VXLAN tunnel endpoints (VTEPs) but the legacy servers are still using traditional VLANs. The team needs to ensure connectivity between the legacy VLAN-based servers and the new VXLAN-based network. What is the best approach to integrate these legacy servers without changing their configuration?

Accepted Answer

Implement a Layer 2 gateway (L2GW) on the leaf switches to bridge VLANs to VXLAN using IRB. An Integrated Routing and Bridging (IRB) interface on the leaf switch acts as a Layer 2 gateway (L2GW), bridging the legacy VLAN to a VXLAN segment. This allows the legacy server, which still uses traditional VLAN tagging, to communicate with the VXLAN-based fabric without any configuration changes on the server. The IRB interface performs the VLAN-to-VXLAN mapping and handles ARP suppression, enabling seamless integration.

Answer

Create a separate VRF for legacy VLANs and redistribute into BGP EVPN

Answer

Configure the same VLAN on all leaf switches and use VXLAN to stretch the VLAN across the fabric

Answer

Reconfigure the legacy servers to use VXLAN encapsulation

Question 3

A developer calls Cisco DNA Center API to get device details and receives the JSON response shown. The device 'Switch-A' is listed but the status is 'unreachable'. Which Cisco DNA Center API endpoint was most likely used?

Accepted Answer

/dna/intent/api/v1/network-device/{id}. The endpoint /dna/intent/api/v1/network-device/{id} retrieves detailed information for a specific network device, including its management IP address, reachability status, and other attributes. The JSON response showing 'Switch-A' with status 'unreachable' indicates a single-device query, which matches the path parameter {id} used to target a particular device. This endpoint returns a device-level status field (e.g., 'reachabilityStatus') that directly reflects the 'unreachable' value seen in the response.

Answer

/dna/intent/api/v1/site/{siteId}/device

Answer

/dna/intent/api/v1/device-health

Answer

/dna/intent/api/v1/network-device

Question 4

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 5

Which TWO of the following are valid OAuth 2.0 grant types? (Select TWO)

Accepted Answer

Client credentials. Authorization code and client credentials are standard grant types. Basic is not OAuth 2.0. API key is a different authentication method. Implicit is deprecated.

Answer

API key

Answer

Basic authentication

Answer

Implicit grant

Question 6

A DevOps engineer is automating network device configuration using Ansible. The playbook must retrieve the MAC address table from a Cisco switch. Which protocol should the engineer use to fetch this data?

Accepted Answer

SNMP. E is correct because SNMP (Simple Network Management Protocol) is specifically designed for reading operational data like MAC address tables from network devices. The engineer can use SNMP GET requests to query the dot1dTpFdbTable (RFC 1493) or the BRIDGE-MIB to retrieve MAC address entries from a Cisco switch efficiently without requiring CLI parsing or web interfaces.

Answer

SSH with CLI scraping

Answer

HTTPS with Web UI

Answer

REST API

Answer

NETCONF

Question 7

A network engineer needs to create a new subnet that can support at least 50 usable host addresses for a development environment. Which TWO subnet masks would meet this requirement? (Choose two.)

Accepted Answer

255.255.255.128 (/25). (255.255.255.128 /25) provides 126 usable host addresses (2^(32-25) - 2 = 126), which exceeds the requirement of 50. Option C (255.255.255.192 /26) provides 62 usable host addresses (2^(32-26) - 2 = 62), also meeting the requirement. Both masks are valid because they yield at least 50 usable IPs for the development subnet.

Answer

255.255.255.224 (/27)

Answer

255.255.255.248 (/29)

Answer

255.255.255.240 (/28)

Question 8

An organization uses Cisco DNA Center and wants to use its Intent API to retrieve the health score of all wireless clients. Which API endpoint and method should be used?

Accepted Answer

GET /dna/intent/api/v1/client-health. The Intent API for retrieving client health scores uses the GET HTTP method on the `/dna/intent/api/v1/client-health` endpoint. This endpoint returns the aggregated health data for all wireless clients, aligning with the read-only nature of the operation and the Intent API's resource-oriented design.

Answer

PUT /dna/intent/api/v1/client-health

Answer

GET /api/v1/health

Answer

POST /dna/intent/api/v1/client-detail

Question 9

A Python script needs to iterate over a dictionary of network interfaces and print each interface name and its IP address. The dictionary is structured as: {'GigabitEthernet1/0/1': '10.1.1.1', 'GigabitEthernet1/0/2': None}. Which THREE code snippets correctly iterate and print the key-value pairs, skipping entries with None? (Choose three.)

Accepted Answer

for iface, ip in interfaces.items():
    if ip != None:
        print(f'{iface}: {ip}'). Options A, B, and D correctly iterate over the dictionary, skip entries where the IP is None, and print the key-value pairs. Option E uses truthiness to skip None, but that would also skip other falsy values like an empty string, and the print with commas adds spaces around the colon, making the output format inconsistent. Option C does not skip None and prints the value as the string 'None'.

Answer

for iface in interfaces.keys():
    print(iface + ': ' + interfaces.get(iface))

Answer

for iface in interfaces:
    if interfaces[iface]:
        print(iface, ':', interfaces[iface])

Question 10

A CI/CD pipeline for a microservice application includes stages: code commit, build Docker image, push to registry, deploy to staging, run integration tests, and deploy to production. The team wants to ensure that if integration tests fail, the pipeline stops and does not proceed to production. Which CI/CD concept is used to enforce this behavior?

Accepted Answer

Stage gates. Stage gates are conditional checkpoints in a CI/CD pipeline that evaluate predefined criteria before allowing the pipeline to proceed to the next stage. In this scenario, the integration test stage acts as a gate: if the tests fail, the gate blocks the pipeline from advancing to the production deployment stage, ensuring only validated code reaches production.

Answer

Rolling update

Answer

Container orchestration

Answer

Artifact management

Question 11

Given the Python list comprehension: result = [x*2 for x in range(10) if x > 5]
What is the value of result?

Accepted Answer

[12, 14, 16, 18]. The list comprehension `[x*2 for x in range(10) if x > 5]` iterates over `x` from 0 to 9, filters to only include `x` values greater than 5 (i.e., 6, 7, 8, 9), and multiplies each by 2, producing `[12, 14, 16, 18]`. This is a standard Python comprehension with a conditional filter.

Answer

[0, 2, 4, 6, 8, 10, 12, 14, 16, 18]

Answer

[10, 12, 14, 16, 18]

Answer

[6, 7, 8, 9]

Question 12

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

Accepted Answer

Proactively detect client connectivity issues.. 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 13

Which TWO of the following are characteristics of TLS (Transport Layer Security) used in HTTPS? (Choose two.)

Accepted Answer

It uses asymmetric encryption to exchange a symmetric session key.. TLS provides encryption and uses certificates for authentication. HTTP/2 is an application layer protocol, not a TLS feature. Port 443 is the default for HTTPS, but TLS itself does not define the port. TLS uses symmetric encryption for session keys.

Answer

It supports multiplexing of multiple streams.

Answer

It is an application layer protocol like HTTP.

Answer

It uses port 443 by default.

Question 14

A Kubernetes pod needs to read configuration data such as database hostname, which is non-sensitive and may change across environments. Which resource should be used to store this data and inject it into the pod?

Accepted Answer

ConfigMap. ConfigMap stores non-sensitive configuration data. Secret stores sensitive data. Deployment and Service are for workload and networking.

Answer

Deployment

Answer

Secret

Answer

Service

Question 15

Which TCP flag is set in the second step of the three-way handshake?

Accepted Answer

SYN and ACK. The TCP three-way handshake begins with the client sending a SYN segment to initiate a connection. In the second step, the server responds with a SYN-ACK segment, which both acknowledges the client's SYN (using the ACK flag) and synchronizes its own sequence number (using the SYN flag). This combined flag is essential for establishing a reliable, bidirectional connection.

Answer

ACK

Answer

SYN

Answer

FIN

Question 16

In the TCP three-way handshake, which sequence of flags is exchanged to establish a connection?

Accepted Answer

SYN, SYN-ACK, ACK. The TCP three-way handshake consists of SYN, SYN-ACK, ACK.

Answer

SYN, ACK, SYN-ACK

Answer

ACK, SYN, SYN-ACK

Answer

SYN-ACK, SYN, ACK

Question 17

Refer to the exhibit. A Python script uses the YANG model to configure the interface. After applying this JSON payload via a PATCH request, what is the expected operational state of the interface?

Accepted Answer

Administratively down. The PATCH request applies the provided JSON payload, which sets the interface's 'enabled' leaf to 'false' (or equivalent YANG leaf for administrative state). In YANG models for interfaces (e.g., RFC 8343 or Cisco native models), setting 'enabled' to false places the interface in an administratively down state. The PATCH operation is valid for modifying interface configuration, and the payload explicitly changes the administrative state to down, overriding any previous configuration.

Answer

Error because PATCH is not allowed on interfaces

Answer

No change, remains as previously configured

Answer

Administratively up and protocol up

Question 18

Which authentication flow is most appropriate for a native mobile app that needs to access the Webex API on behalf of a user?

Accepted Answer

Authorization code grant. The authorization code grant is designed for apps that can securely store a client secret, but for native apps, PKCE (Proof Key for Code Exchange) is recommended. However, among standard grants, authorization code is the correct choice for user delegation.

Answer

Client credentials grant

Answer

Resource owner password grant

Answer

Implicit grant

Question 19

Refer to the exhibit. A developer is parsing the output of 'show ip route' using Python. Which regular expression would extract the prefix '10.0.1.0/24'?

Accepted Answer

r'^S\s+(\d+\.\d+\.\d+\.\d+/\d+)'. The regex `^S\s+(\d+\.\d+\.\d+\.\d+/\d+)` matches lines starting with 'S' (static route) followed by whitespace, then captures the entire prefix including both the IP address and subnet mask in CIDR notation (e.g., 10.0.1.0/24). This ensures the extracted string is exactly the prefix as it appears in the 'show ip route' output.

Answer

r'^S\s+(\d+\/\d+)'

Answer

r'^S.*(\d+\.\d+\.\d+\.\d+)'

Answer

r'S\s+(\S+)'

Question 20

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

Accepted Answer

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

Answer

POST

Answer

PUT

Answer

UPDATE