CCNA Automation (200-901). Set it up and run it.

1. Refer to the exhibit. A developer runs this Python code expecting to change the first element of the tuple. What happens when the interpreter executes the second line?

• A. It silently updates the first element to 15
• B. It raises a TypeError because tuples are immutable
• C. It appends the value 15 as a new element
• D. It converts the tuple into a mutable list

Correct answer: B. Tuples are immutable, so item assignment like coords[0] = 15 is not allowed and the interpreter raises a TypeError stating that tuple objects do not support item assignment. The value cannot be changed in place.

Why the others are wrong. Silently updating the element would require mutability, which tuples lack. Appending is impossible because tuples have no append method and cannot grow. Python never automatically converts a tuple to a list on assignment; the developer would have to build a new tuple or use a list from the start.

2. Refer to the exhibit. A POST to create a device keeps failing. Which two additions to this request are required to send an authenticated JSON creation successfully? (Choose two.)

• A. A Retry-After header set to 60 seconds
• B. A 200 OK status line in the request
• C. An X-RateLimit-Limit header from the client
• D. An Authorization header carrying a valid token
• E. A Content-Type: application/json header

Correct answer: D. An authenticated JSON creation needs an Authorization header carrying a valid token so the server accepts the identity, and a Content-Type: application/json header so the server parses the body as JSON.

Why the others are wrong. Retry-After is a response header sent by the server during throttling, not something a client adds to a request. A status line belongs in a response, not a client request. X-RateLimit-Limit is server-provided rate metadata and is not required to authenticate or create a resource.

3. A developer assigns config = {'host': 'api.example.com', 'port': 443} in Python. What built-in data type does the variable config reference after this assignment?

• A. set
• B. list
• C. tuple
• D. dict

Correct answer: D. Curly braces enclosing comma-separated key-value pairs create a dict, Python's built-in mapping type; here the keys 'host' and 'port' map to their values, so config references a dictionary object.

Why the others are wrong. A set also uses curly braces but holds only single values with no colons, so the key-value pairs rule it out. A list uses square brackets and holds ordered values, not mappings. A tuple uses parentheses and is immutable, so neither list nor tuple matches the braces-and-colons syntax shown.

4. An application needs to retrieve a list of existing device resources from a REST API without changing any server state. Which HTTP method fits this operation?

• A. GET
• B. POST
• C. PUT
• D. DELETE

Correct answer: A. GET retrieves a representation of a resource and is a safe, read-only method that does not modify server state, making it the correct choice for fetching an existing list of devices.

Why the others are wrong. POST creates a new resource or submits data for processing and can change server state, so it is not read-only. PUT replaces an entire resource and is used for updates, not retrieval. DELETE removes a resource, which also alters state and discards data rather than reading it.

5. Refer to the exhibit. A POST to /dna/system/api/v1/auth/token on Catalyst Center returned this body. Which header must subsequent Intent API requests include to authenticate?

• A. X-Auth-Token: TOKEN
• B. Authorization: Bearer TOKEN
• C. X-Cisco-Meraki-API-Key: TOKEN
• D. Cookie: APIC-cookie=TOKEN

Correct answer: A. The token returned by the auth endpoint is presented on every later Intent API call in the X-Auth-Token header; without it the controller responds 401 Unauthorized.

Why the others are wrong. Authorization: Bearer is common in OAuth and some Meraki calls, but Catalyst Center expects its token in X-Auth-Token, not a Bearer scheme. X-Cisco-Meraki-API-Key belongs to the Meraki dashboard, a different platform. Cookie: APIC-cookie is how Cisco ACI's APIC carries its session token.

6. An engineer builds an application into a Docker image and then starts it running on a host. What is the running instance of that image called?

• A. A registry entry
• B. A build layer
• C. A base image
• D. A container

Correct answer: D. A container is a running, isolated instance created from a read-only image; the image is the static template, while the container adds a thin writable layer and runs as a process. Many containers can start from one image.

Why the others are wrong. A registry entry is where images are stored and distributed, not a running process on the host. A build layer is one cached filesystem change inside an image, not the runtime unit. A base image is the starting FROM image a build extends, still static and not executing.

7. An engineer manages device configuration by writing definition files that are stored in a Git repository and applied by a tool, instead of editing each device by hand. Which practice does this describe?

• A. Screen scraping the device CLI
• B. Out-of-band console management
• C. Infrastructure as Code
• D. Manual device-by-device editing

Correct answer: C. Infrastructure as Code treats configuration as versioned definition files applied by tooling, giving repeatable, reviewable, and automated device management rather than manual, one-off changes made directly on each device.

Why the others are wrong. Screen scraping the CLI parses unstructured terminal output and is fragile, not a definition-file practice. Out-of-band console management is a physical access path for reaching a device, unrelated to how configuration is authored. Manual device-by-device editing is exactly the ad hoc approach that Infrastructure as Code replaces with versioned, tool-applied definitions.

8. A script runs ports = [22, 80]; ports.append(443) and then prints the list. What does the variable ports contain after the append call executes?

• A. [22, 80, 443]
• B. [22, 80]
• C. [443, 22, 80]
• D. [22, 443, 80]

Correct answer: A. The list append method mutates the existing list in place by adding the argument as a new last element, so ports grows from two elements to [22, 80, 443] while keeping its original order intact.

Why the others are wrong. [22, 80] ignores the append entirely and shows the original list. [443, 22, 80] wrongly inserts the new value at the front, but append never prepends. [22, 443, 80] places the value in the middle, which no append operation does; append always adds to the end.