>DevOps Interview KB

Senior DevOps Interview Questions

516 questions across 39 categories

Deeper trade-off and design questions — why a specific approach was chosen, what breaks at scale, and how to reason about a system you didn't build.

How would you tune a hedge-request delay so it targets genuine cold-start tail latency without firing on every normal request?

AdvancedAWSLambda7 min

How would you audit all S3 buckets in an account for their current Block Public Access and policy configuration, at scale?

AdvancedAWSS37 min

How would you handle the allowlisting process for intentionally-public S3 buckets so it doesn't become its own source of friction or forgotten debt?

IntermediateAWSS36 min

What's the difference between S3 Block Public Access and a restrictive bucket policy, and why is Block Public Access the stronger tool during an active exposure incident?

IntermediateAWSS36 min

What's the difference between S3's 'block public ACLs' and 'restrict public buckets' as individual Block Public Access settings?

IntermediateAWSS36 min

How would you decide whether an S3 public-write exposure is a supply-chain security incident requiring broader notification, versus a contained issue?

AdvancedAWSS37 min

How would you determine, after an S3 public-write exposure, exactly which objects were added, modified, or deleted if versioning wasn't enabled?

AdvancedAWSS37 min

How would you measure whether an S3 public-exposure alerting system is actually working, short of waiting for a real incident?

IntermediateAWS6 min

What preventive controls would make an S3 public-write exposure incident less damaging in the future — bucket policies, Object Lock, or something else?

IntermediateAWSS36 min

A security scanner just flagged one of your production S3 buckets as publicly readable. Walk through how you'd respond in the first hour and prevent a repeat.

AdvancedAWSS3Security10 min

How would you design alerting so a public S3 exposure is caught within minutes, rather than being discovered by an external scanner or a customer report?

AdvancedAWSS38 min

How would your incident response differ if an exposed S3 bucket allowed public write access, not just public read?

AdvancedAWSS38 min

Why might an organization choose not to enable account-level S3 Block Public Access by default, and what legitimate use case would that block?

IntermediateAWSS36 min