Walmart Global Tech Cloud Platforms & Architecture interview questions

Turns the standard autoscaling definition into the problem it actually causes. Almost every candidate can define an HPA; far fewer can say why theirs did not save them.

A design question with a clear answer at this scale, and the reasoning is what scores. The three options solve different problems and peering and Transit Gateway connect networks while PrivateLink exposes services.

Trace the route and return path before changing rules. First establish whether the failing connection uses IPv4, IPv6 or a private service endpoint.

S3 access failures are rarely about the bucket policy alone. The caller, object ownership and network path determine which authorization checks apply. Start with the failed request and trace changes across those boundaries.

Spreading instances across availability zones is not the same as surviving an AZ failure. The candidates who know this can name the four coupling points that quietly re-unify your blast radius.

The services-and-enterprise interview staple. There is a defensible answer and it is not 'always re-platform': the decision is a function of change tolerance, deadline reality and what the workload is worth.

The cheapest storage class is rarely the cheapest answer. Retrieval pricing, minimum durations and per-transition fees decide whether a lifecycle rule saves money or manufactures waste.

A busy date key can throttle while table capacity remains available. Check the actual key distribution and throttling reason before adding capacity or shards.

Fleet-wide replacement is a traffic-shaping problem: bake once, wave through in controlled batches, watch the alarms, and keep the exit open. In-place patching is the alternative and usually the regret.

Hybrid DNS fails in both directions independently. Outbound rules carry VPC queries to your data centre, inbound endpoints bring on-prem queries back here, and both halves need wiring.

Account-per-team is the right instinct, but hand-rolled account setup drifts within a month. Vending turns governance into a pipeline with an SLA instead of a ticket queue.

Guaranteed capacity and discounted capacity are different products. Peak season needs both, arranged in layers and verified with a game day before the traffic arrives.

Data transfer is charged in several unrelated ways and reported as one line, so the first job is decomposition. Most surprises are cross-zone chatter between services that never needed to be on different nodes.

Moving a Kubernetes service account changes its token subject. Separate pod mutation, federation trust and Key Vault authorization before adding permissions.

Asked in almost every cloud screen, and most candidates recite the table without ever naming the failure it causes. The ephemeral port range is the whole answer.

The question that separates console users from people who have debugged a permissions failure across accounts. Evaluation order is deterministic and knowing it makes AccessDenied readable.

Most candidates can sell serverless. The question asks you to argue against it, which needs a real understanding of the execution model rather than the marketing.

The junior-filter question that still separates candidates who understand the model from those who memorised a definition. The answer is three mechanical differences and one economic one.

Database redundancy still needs reconnecting clients. Distinguish the deployment type, then measure how promotion and DNS changes affect application requests.

DNS failover is a blunt instrument with three delays stacked on top of each other: detection, propagation and client caching. Knowing their sizes tells you when DNS is the right layer at all.