Q11) Partial vs. full updates over RESTCONF
You need to change only the description of interface GigabitEthernet1 using the standard ietf-interfaces model. Which HTTP method is most appropriate?
A. PUT the full interface resource
B. PATCH the specific interface with only the description in the body
C. POST to /restconf/operations/ietf-interfaces:interfaces
D. DELETE and recreate the interface with POST
Detailed Explanation: PATCH performs a partial update on the targeted resource, whereas PUT replaces the entire resource. POST is for creation or RPC operations; DELETE removes the resource.
Q12) NETCONF filtering for selective retrieval
You must fetch only the descriptions of interfaces whose names start with “GigabitEthernet” via a single <get> request. Which filter type best fits?
A. No filter (retrieve everything)
B. Subtree filter
C. XPath filter
D. JSON filter
Detailed Explanation: XPath filters allow expression-based selection (e.g., name starts-with) in a single <get>. Subtree filters match explicit structure but not pattern logic.
Q13) HTTP status when DNA Center token expires
Your script calls Cisco DNA Center’s REST API with an expired access token. Which HTTP status code should you expect?
A. 200 OK
B. 401 Unauthorized
C. 403 Forbidden
D. 429 Too Many Requests
Detailed Explanation: 401 Unauthorized indicates missing/invalid/expired credentials. 403 means valid credentials but insufficient permissions; 429 is rate limiting.
Q14) gNMI encoding choice for human-readable payloads
You want telemetry updates in a human-readable JSON format that aligns with IETF JSON encoding of YANG data. Which gNMI encoding should you request?
A. BYTES
B. PROTO
C. JSON_IETF
D. ASCII
Detailed Explanation: JSON_IETF provides RFC-style JSON mapping for YANG data, making it readable and interoperable. PROTO/BYTES are efficient but not human-friendly.
Q15) YANG modeling for referential integrity
A service model needs a leaf that references an existing interface name in another part of the data tree to ensure only valid interfaces are chosen. Which YANG statement is designed for this?
A. must
B. when
C. leafref
D. identityref
Detailed Explanation: leafref creates a pointer to another leaf’s value, enforcing referential integrity. must/when are constraints; identityref refers to identities, not instance values.
