This is my first post here, not sure if its in the right category! I have final interview rounds with AWS for a Network Development Engineer role coming up next week and the Design interview will have questions like the 2 examples I have shared below. I’m a CCNA R&S who worked at Cisco for 7 years with concentration in Data center operations, but mostly in a troubleshooting role and barely did any design. I’m looking for advice on how one would approach and brainstorm the questions:
2 hour interview - will require you to design a network component or network related large-scale system.
Example 1: Design a network for large scale data center network (Ask about economics, scale, redundancy models etc). Follow up: upgrade to 2 DC’s and interconnect them How would you monitor the network?
Example 2: Build an automated network design framework
Example 3: Design a network for 10k+. (Ask about economics, scale, redundancy models etc). Follow up: upgrade to 20k+. How would you monitor the network?
Any help with this (even things like questions I might ask for clarifying the scenario or core ideas to keep in mind) would be greatly appreciated! I’m aware of architectures like 3 layer for campus and spine-leaf for data center, but not sure how to structure my approach since it is a pretty open ended question.
Welcome to the forum! Your post is just fine here in a new topic, since it’s not specific to a particular lesson. The truth is, the guidance you’re looking for goes beyond what our lesson content here at Networklessons.com is designed to cover. Our courses focus primarily on Cisco certification exam prep and foundational networking concepts. However, I can share with you what I would like to see from an interviewee if I were the interviewer asking these questions. Hopefully it will be insightful for you.
These are purposfully set up as open ended questions, and they’re designed to evaulate your critical thinking. A good way to structure responses to these open-ended questions is to avoid jumping straight into a topology.
Start by clarifying the requirements: number and type of endpoints, traffic patterns, bandwidth and latency needs, growth expectations, availability targets, budget, security, and operational constraints.
Then explain your assumptions and work through the design in layers: physical topology, routing, redundancy and failure domains, addressing, capacity planning, automation, monitoring, and upgrade strategy.
For a large data center, you would likely discuss a spine-leaf architecture, ECMP, scalable routing such as BGP, redundant links and devices, and how the design expands from one site to two.
For monitoring, cover telemetry, logs, flow data, synthetic tests, alerting, capacity trends, and automated validation.
The interviewers are usually evaluating your reasoning, trade-offs, and ability to ask the right questions more than the actual outcome of your suggested design. They want to see more of how you think, and less of what the end result will be.