Cisco 350-501 Practice Test 63
Question 620
For an original SPCOR service-provider engineering scenario, consider: A PE automation client uses HTTP GET to modify an interface address through a RESTCONF data resource and wonders why no state changes. Select TWO complementary steps: the targeted correction and its strongest prechange validation.
- Check: Check state addresses, lock contention, plan create-update-destroy actions and expected controller changes in a sandbox.
- Change: Align exporter and collector template handling, source interface, sampling and timeout settings, then validate interpreted flow fields.
- Check: Inspect capabilities, URL module prefix, requested HTTP method, Content-Type and returned status with a nonproduction test interface.
- Change: Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies.
- Post arbitrary plaintext IOS CLI to every RESTCONF endpoint and assume a 200 response is guaranteed.
Explanation
Correct Answer
C:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. Acceptance: Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors.
D:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. Evidence: Inspect capabilities, URL module prefix, requested HTTP method, Content-Type and returned status with a nonproduction test interface.
Incorrect Answers
A:Check: Check state addresses, lock contention, plan create-update-destroy actions and expected controller changes in a sandbox. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
B:Change: Align exporter and collector template handling, source interface, sampling and timeout settings, then validate interpreted flow fields. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
E:For this select two assessment, the shortcut changes or bypasses the necessary routing, service or operational boundary rather than correcting it. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
Question 621
A service provider network engineer is reviewing this backbone or customer-service scenario: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response. A proposed shortcut is: Post arbitrary plaintext IOS CLI to every RESTCONF endpoint and assume a 200 response is guaranteed. What should the service provider engineer recommend as the narrowly scoped correction? Select ONE best answer.
- Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies.
- Post arbitrary plaintext IOS CLI to every RESTCONF endpoint and assume a 200 response is guaranteed.
- Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types.
- Normalize model identifiers, timestamps and collector health across gNMI, flow and management telemetry before declaring a backbone service incident.
Explanation
Correct Answer
A:This targeted action addresses the observed service-provider control or forwarding gap without discarding necessary controls. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
Incorrect Answers
B:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. Use this instead: Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies.
C:Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
D:Normalize model identifiers, timestamps and collector health across gNMI, flow and management telemetry before declaring a backbone service incident. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
Question 622
A Cisco service provider design review finds: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response. The team proposes: Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies. Which engineering principle most strongly supports the recommended response? Select ONE best answer.
- RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
- YANG defines containers lists keys and typed leaves, allowing supported protocol clients to validate configuration independently of arbitrary CLI text layouts.
- gRPC carries typed RPC streams, while gNMI supports model-based telemetry and configuration; TLS and mTLS protect and authenticate session peers.
- SNMPv3 security models can provide authenticated and private management traffic; v2c communities do not themselves encrypt or strongly authenticate messages.
Explanation
Correct Answer
A:Demonstrable success requires: Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors. This principle explains the proposed technical approach, which is: Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies.
Incorrect Answers
B:YANG defines containers lists keys and typed leaves, allowing supported protocol clients to validate configuration independently of arbitrary CLI text layouts. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
C:GRPC carries typed RPC streams, while gNMI supports model-based telemetry and configuration; TLS and mTLS protect and authenticate session peers. A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response.
D:SNMPv3 security models can provide authenticated and private management traffic; v2c communities do not themselves encrypt or strongly authenticate messages. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
Question 623
The service provider operations team has not yet approved a change. Current evidence indicates: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response. Which evidence best tests the technical diagnosis before approving a disruptive change? Select ONE best answer.
- Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification.
- Check state addresses, lock contention, plan create-update-destroy actions and expected controller changes in a sandbox.
- Inspect capabilities, URL module prefix, requested HTTP method, Content-Type and returned status with a nonproduction test interface.
- Trace one known link flap across device clock, gNMI update, IPFIX flow record and monitoring event with ingestion-lag checks.
Explanation
Correct Answer
C:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. Confirm afterward that: Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors.
Incorrect Answers
A:Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
B:Check state addresses, lock contention, plan create-update-destroy actions and expected controller changes in a sandbox. A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response.
D:Trace one known link flap across device clock, gNMI update, IPFIX flow record and monitoring event with ingestion-lag checks. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
Question 624
A candidate correction has been tested and the platform team requires a post-change acceptance check. Original problem: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response. The carrier operations owner needs positive and negative tests showing existing customer services remain available. Which acceptance result demonstrates correct service provider forwarding and control behavior without disrupting authorized workflows? Select ONE best answer.
- Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors.
- The service converges consistently or exposes a recoverable failure without silent partial configuration across customers.
- Reviewed plans converge expected resources without conflicting state writes or unapproved destructive network actions.
- Only valid transactions enter the intended configuration datastore and any commit failure is clearly reported and rolled back where supported.
Explanation
Correct Answer
A:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. Applied case: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response.
Incorrect Answers
B:The service converges consistently or exposes a recoverable failure without silent partial configuration across customers. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
C:Reviewed plans converge expected resources without conflicting state writes or unapproved destructive network actions. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
D:This option addresses a different service provider engineering topic (NETCONF edit-config candidate commit and error handling) rather than the documented RESTCONF HTTP methods and YANG data resources decision.
Question 625
An implementation sign-off request identifies the following problem: A script posts malformed JSON with a missing module-qualified key to a valid RESTCONF URI and retries indefinitely after a 400 response. Which paired technical change and validation should close the implementation review? Select ONE best answer.
- Change: Use documented SNMP access restrictions and authenticated encrypted SNMPv3 where supported and verify polling and notifications separately. Verify: Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification.
- Change: Keep state in an access-controlled locked backend and review plans and drift against provider-supported network resources before apply. Verify: Check state addresses, lock contention, plan create-update-destroy actions and expected controller changes in a sandbox.
- Change: Select supported RESTCONF data paths and HTTP operations, preserve YANG schema types and handle documented status and error bodies. Verify: Inspect capabilities, URL module prefix, requested HTTP method, Content-Type and returned status with a nonproduction test interface.
- Change: Normalize model identifiers, timestamps and collector health across gNMI, flow and management telemetry before declaring a backbone service incident. Verify: Trace one known link flap across device clock, gNMI update, IPFIX flow record and monitoring event with ingestion-lag checks.
Explanation
Correct Answer
C:RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation. The change is successful only when: Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors.
Incorrect Answers
A:Change: Use documented SNMP access restrictions and authenticated encrypted SNMPv3 where supported and verify polling and notifications separately. RESTCONF maps YANG-modeled resources to HTTP semantics; a valid TCP connection cannot replace correct method, content type or schema validation.
B:Change: Keep state in an access-controlled locked backend and review plans and drift against provider-supported network resources before apply.
D:Change: Normalize model identifiers, timestamps and collector health across gNMI, flow and management telemetry before declaring a backbone service incident.
Question 626
A service provider network engineer is reviewing this backbone or customer-service scenario: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails. A proposed shortcut is: Claim a shell loop performing separate SSH commands gives the same service-level atomicity as modeled orchestration. What should the service provider engineer recommend as the narrowly scoped correction? Select ONE best answer.
- Use documented SNMP access restrictions and authenticated encrypted SNMPv3 where supported and verify polling and notifications separately.
- Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types.
- Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior.
- Claim a shell loop performing separate SSH commands gives the same service-level atomicity as modeled orchestration.
Explanation
Correct Answer
C:This targeted action addresses the observed service-provider control or forwarding gap without discarding necessary controls. Applied case: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails.
Incorrect Answers
A:Use documented SNMP access restrictions and authenticated encrypted SNMPv3 where supported and verify polling and notifications separately. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
B:Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
D:NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion. For this best change assessment, the shortcut changes or bypasses the necessary routing, service or operational boundary rather than correcting it.
Question 627
A Cisco service provider design review finds: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails. The team proposes: Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior. Which engineering principle most strongly supports the recommended response? Select ONE best answer.
- NetFlow and IPFIX export summarized flow records whose field templates and sampling rules determine what collectors can reconstruct.
- NETCONF uses modeled XML RPC messages and datastore operations; an active SSH transport or accepted candidate does not necessarily mean a committed change.
- NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
- Ansible hosts and groups determine the execution scope while modules and conditions can converge device configuration without uncontrolled repeated changes.
Explanation
Correct Answer
C:Demonstrable success requires: The service converges consistently or exposes a recoverable failure without silent partial configuration across customers. This principle explains the proposed technical approach, which is: Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior.
Incorrect Answers
A:NetFlow and IPFIX export summarized flow records whose field templates and sampling rules determine what collectors can reconstruct. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
B:NETCONF uses modeled XML RPC messages and datastore operations; an active SSH transport or accepted candidate does not necessarily mean a committed change. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
D:Ansible hosts and groups determine the execution scope while modules and conditions can converge device configuration without uncontrolled repeated changes. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
Question 628
The service provider operations team has not yet approved a change. Current evidence indicates: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails. Which evidence best tests the technical diagnosis before approving a disruptive change? Select ONE best answer.
- Trace one known link flap across device clock, gNMI update, IPFIX flow record and monitoring event with ingestion-lag checks.
- Inspect modeled service inputs, dry-run target diffs, device transaction outcomes and an injected failure during a lab provision.
- Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification.
- Run check mode or an isolated deployment twice, comparing targeted hosts, command diff, failed hosts and change counts.
Explanation
Correct Answer
B:NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion. Applied case: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails.
Incorrect Answers
A:Trace one known link flap across device clock, gNMI update, IPFIX flow record and monitoring event with ingestion-lag checks. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
C:Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
D:Run check mode or an isolated deployment twice, comparing targeted hosts, command diff, failed hosts and change counts. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
Question 629
A candidate correction has been tested and the platform team requires a post-change acceptance check. Original problem: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails. The carrier operations owner needs positive and negative tests showing existing customer services remain available. Which acceptance result demonstrates correct service provider forwarding and control behavior without disrupting authorized workflows? Select ONE best answer.
- Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors.
- The service converges consistently or exposes a recoverable failure without silent partial configuration across customers.
- New devices enroll only with trusted artifacts and unique approved identities, and unexpected bootstrap sources are rejected.
- Reviewed plans converge expected resources without conflicting state writes or unapproved destructive network actions.
Explanation
Correct Answer
B:NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion. The approved implementation step was: Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior.
Incorrect Answers
A:Read and write requests affect only approved modeled resources and invalid payloads receive specific diagnosable errors. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
C:New devices enroll only with trusted artifacts and unique approved identities, and unexpected bootstrap sources are rejected. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
D:Reviewed plans converge expected resources without conflicting state writes or unapproved destructive network actions. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
Question 630
For an original SPCOR service-provider engineering scenario, consider: A provider provisions a multi-device EVPN service by issuing CLI snippets independently and cannot identify which sites were changed after the third router fails. Select TWO complementary steps: the targeted correction and its strongest prechange validation.
- Change: Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types.
- Check: Inspect modeled service inputs, dry-run target diffs, device transaction outcomes and an injected failure during a lab provision.
- Change: Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior.
- Check: Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification.
- Claim a shell loop performing separate SSH commands gives the same service-level atomicity as modeled orchestration.
Explanation
Correct Answer
B:NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion. Required intervention: Represent service intent using supported Cisco NSO models and dry-run transactional changes and validate device diffs and recovery behavior.
C:NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion. Acceptance: The service converges consistently or exposes a recoverable failure without silent partial configuration across customers.
Incorrect Answers
A:Change: Use the platform's published YANG module and typed hierarchical schema to construct data operations with validated paths and leaf types. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
D:Check: Inspect security level, user and engine parameters, permitted managers, packet captures and a representative interface counter query and notification. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
E:For this select two assessment, the shortcut changes or bypasses the necessary routing, service or operational boundary rather than correcting it. NSO can map a service model to multi-device configuration with controlled transactions, enabling auditable service-level creation, modification and deletion.
