DevOps & Cloud Interview Prep: Real Scenarios & Answers

Blocking zero-day exploits in container runtimes means layering seccomp, AppArmor, and eBPF LSM hooks — and knowing exactly where each one fits in the kernel's enforcement chain. You'll learn: How seccomp profiles restrict syscall surfaces and which calls are most dangerous to leave open in container workloads Writing and applying AppArmor profiles to constrain file, network, and capability access...

Forecasting cloud spend for a generative AI workload means dealing with wildly variable GPU instance costs, token-based API charges, and inference traffic spikes — here's how to model it with the AWS Cost Explorer API and Facebook Prophet. You'll learn: How to pull historical cost data via the AWS Cost Explorer API using get_cost_and_usage with granularity and filter parameters scoped to your GenA...

Secret scanning with Gitleaks and pre-commit hooks is your last line of defence before AWS credentials hit a public GitHub repo — here's how to set it up properly in CI. You'll learn: How to install and configure Gitleaks to scan for AWS keys, tokens, and other secrets before a commit lands Why pre-commit hooks catch leaks that CI pipeline scans miss — and how to wire both together What to do when...

Learn how to implement VPC flow log anomaly detection by combining Amazon Detective's graph-based investigation with Athena ML queries to surface real network threats. You'll learn: How Amazon Detective ingests VPC flow logs and builds behavior baselines using machine learning automatically Writing Athena ML USING FUNCTION queries against flow log data in S3 to flag statistical outliers in traffic...

Architecting a single Karpenter cluster for ML, Backend, and Batch teams means getting NodePool weights and taint-based isolation right — or pods land somewhere expensive and wrong. You'll learn: How to define separate NodePools per team — ml-gpu (p3/p4 instances), backend (m5/m6), and batch-spot (Spot, any family) How Karpenter's spec.weight field drives pool selection: higher weight wins, ties b...

When your security team mandates a specific AMI, private subnets, custom security groups, and encrypted EBS, Karpenter's EC2NodeClass is exactly where all of that infrastructure detail lives. You'll learn: The core separation of concerns: NodePool defines what to provision (requirements, constraints); EC2NodeClass defines how (the cloud-provider infrastructure details) How to pin a specific AMI us...

Your cluster is burning 50 nodes at 10% utilization at 2 AM with a stale AMI — here's exactly how Karpenter's disruption engine handles both problems automatically. You'll learn: Setting consolidationPolicy: WhenEmptyOrUnderutilized with a consolidateAfter: 30s window to drain and terminate underutilized nodes How Karpenter's drift detection compares live node spec against the current NodeClass —...

A pending ML training job needing 8 GPUs is a classic Karpenter interview scenario — here's the exact four-step lifecycle an interviewer expects you to walk through. You'll learn: Why the K8s scheduler marks pods unschedulable and how Karpenter's controller watches for that signal How Karpenter evaluates all pod constraints at once — resource requests, nodeSelector, nodeAffinity, tolerations, and...

Migrating a stateful .NET app from Azure VMs to Azure Container Apps without dropping a single request — including SQL Server Always On AG failover — is exactly the kind of scenario senior interviewers throw at platform engineers. You'll learn: How to containerize a stateful .NET app and handle session/state externalization before cutover Azure Container Apps environment setup: managed environment...

Scaling Argo CD across 100+ teams demands more than one cluster — this episode breaks down how to architect multi-tenant Argo CD with SSO, cluster sharding, and hard namespace boundaries. You'll learn: How to integrate SSO (Dex/OIDC) with Argo CD RBAC to enforce per-team access without shared admin credentials When and how to shard Argo CD across multiple Application Controllers to avoid reconcili...

When legacy workloads need NET_RAW, blanket Pod Security Admission enforcement breaks them — this episode walks through using Kyverno mutation policies to handle the exception without weakening your cluster-wide baseline. You'll learn: Why NET_RAW is dropped by the Kubernetes restricted and baseline PSA profiles and what that breaks in practice How to write a Kyverno mutate policy that injects a s...

Cold start mitigation for Java 21 Lambda at 50K RPS is one of the most punishing interview questions for senior cloud engineers — here's how to compare the three real options without hand-waving. You'll learn: How SnapStart snapshots the Afterburner-restored JVM state and where it still adds latency on restore Why Provisioned Concurrency keeps execution environments warm but drives up cost at sust...

When eBPF-based security profiles silently block syscalls in a Kata Containers runtime, tracking down 'container not started' errors requires knowing exactly where to look. You'll learn: How Kata Containers' nested virtualization layer changes where failures actually surface versus standard runc Why eBPF security profiles (Seccomp, BPF-LSM) can silently drop syscalls that the guest kernel needs at...

S3 Object Lambda lets you dynamically redact PII from petabytes of legacy data at read time — no ETL pipelines, no data duplication, no migration headaches. You'll learn: How S3 Object Lambda intercepts GetObject calls to transform data on the fly before it reaches the caller Wiring a Lambda function to an Object Lambda Access Point to strip or mask PII fields in real time Why this approach beats...

Latency spikes in an AWS Global Accelerator setup with Direct Connect are notoriously hard to pin down — this episode walks through a structured troubleshooting approach including VPC Flow Logs analysis. You'll learn: How to isolate whether latency originates at the Global Accelerator edge, the Direct Connect path, or inside the VPC Reading VPC Flow Logs to identify packet loss, retransmits, and a...

Architecting zero-trust access to an AKS cluster from on-prem legacy systems is one of those senior interview questions that exposes whether you actually understand the control plane or just know the buzzwords. You'll learn: How Azure Arc projects on-prem and legacy workloads into the Azure control plane without exposing the API server publicly Where OPA Gatekeeper fits — enforcing admission polic...

Securing inter-region data in transit on Google Cloud with post-quantum algorithms like Kyber and Dilithium is fast becoming a senior interview topic — here's how to design it properly. You'll learn: Why NIST-selected algorithms Kyber (key encapsulation) and Dilithium (digital signatures) are the go-to choices for post-quantum TLS on GCP How to layer quantum-resistant encryption over inter-region...

Designing an active-active video processing pipeline across AWS Elemental MediaLive and Azure Media Services — while hitting sub-100ms end-to-end latency — is exactly the kind of system design question that separates senior candidates from the rest. You'll learn: How to architect an active-active topology spanning AWS and Azure without a single-cloud bottleneck State synchronization patterns for k...