Cisco Certified DevNet Professional Advanced Practice Exam: Hard Questions 2025

You are designing a Python SDK for an internal network-automation platform used by multiple teams. The platform exposes REST endpoints that are frequently extended, and consumers want (1) strong typing and discoverability, (2) backward compatibility, and (3) the ability to ship partial feature updates without forcing all teams to upgrade at once. Which design approach best satisfies these requirements?

A microservice orchestrates multi-device changes (IOS XE and NX-OS) via device APIs. The workflow is: validate intent, stage config, commit, then post-check. The business requires that if any device fails commit, all devices must be rolled back to the pre-change state. Devices do not support true distributed transactions, and network partitions can occur during rollback. Which architecture pattern best addresses correctness and recovery while keeping the system scalable?

Your service consumes a Cisco platform REST API that enforces rate limits and returns 429 responses with a Retry-After header. The service is deployed in multiple replicas behind a load balancer, and each replica currently implements exponential backoff independently. Under burst load, you still observe sustained 429s and long tail latency. What is the BEST improvement to reduce 429s while keeping throughput high and behavior predictable?

A webhook receiver processes events from a Cisco platform. The sender will retry delivery on non-2xx responses. Your receiver must guarantee exactly-once side effects (e.g., creating a ticket) even if events are delivered multiple times, arrive out of order, or are replayed after an outage. The event payload includes a unique eventId and a timestamp. What is the most robust design?

You are troubleshooting a service that authenticates to Cisco APIs using OAuth2. In production, token refresh suddenly begins failing intermittently with 401 errors, but only for some pods. Logs show that those pods are using an access token that was minted earlier than the refresh token they are attempting to use. The system uses a shared Redis cache for tokens and rotates client secrets via an external secret manager. What is the most likely root cause and best fix?

Your team automates policy changes on Cisco DNA Center. A job that previously worked starts failing only in one environment after a network change. The failure is: TLS handshake error when calling the controller API endpoint; curl from the same pod shows the server cert chain is now signed by a different intermediate CA. You must restore automation quickly while maintaining strong security. What is the BEST action?

A NetDevOps pipeline uses NSO to deploy services across multiple device families. After a partial outage, NSO shows a service as "in-sync" but devices are not in the intended state. Subsequent redeploy attempts do nothing. You suspect the NSO database reflects the desired state, but the live device state diverged. What is the BEST troubleshooting/remediation sequence to realign NSO and the network while avoiding unintended changes?

A containerized automation service runs in Kubernetes and executes Ansible playbooks that connect to network devices via SSH and NETCONF. In production, pods are OOMKilled during large rollouts, and failures correlate with high parallelism. You need to increase reliability without significantly increasing cluster cost. Which change is MOST effective?

A DevNet application exposes a REST API used to trigger network changes. Security requires: least privilege per client, auditable authorization decisions, and the ability to revoke access quickly without redeploying the app. The app is deployed across multiple environments and integrates with Cisco APIs downstream. Which approach best meets these requirements?

You are building an automation pipeline that uses Terraform to provision cloud networking and then configures on-prem devices using Ansible. Failures occur when Terraform succeeds but Ansible fails mid-run, leaving partially configured devices and breaking subsequent runs due to drift. You need a strategy that improves convergence and supports safe retries. What is the BEST solution?