Kubernetes Interview Questions
128 questions
The most extensive topic on this site: RBAC and security context, storage (PV/PVC/StorageClass), workloads and controllers (Deployments, StatefulSets, DaemonSets, Jobs, CronJobs), autoscaling (HPA/VPA), scheduling and affinity, networking, cluster architecture, CRDs and operators, admission control, and cluster security hardening. Every question is a realistic production scenario — a pod stuck Pending, a webhook silently breaking scheduling, a StatefulSet rollout behaving unexpectedly — not a bare definition.
How does a Service-not-routing-traffic failure mode differ between a plain ClusterIP Service and one fronted by an Ingress controller?
IntermediateKubernetes7 min
How would you troubleshoot connectivity that works within a node but fails between pods on different nodes?
AdvancedKubernetes8 min
How would you design NetworkPolicies for a namespace using default-deny-all while still allowing necessary traffic?
IntermediateKubernetes7 min
What's the difference between Kubernetes Endpoints and EndpointSlices, and why did Kubernetes introduce EndpointSlices?
IntermediateKubernetes6 min
A headless Service behaves completely differently for DNS resolution — what's different, and when do you need it?
IntermediateKubernetes6 min
What's the difference between the older Ingress resource and the newer Gateway API, and when would you actually migrate?
IntermediateKubernetes6 min
A pod resolves a Service's DNS name intermittently but not consistently — how do you investigate CoreDNS itself?
AdvancedKubernetes8 min
How would you migrate a cluster from one CNI plugin to another without a full cluster rebuild — what's actually risky about it?
ExpertKubernetes8 min
What does a pod's ndots DNS setting default to, and how can it cause unexpectedly slow external DNS lookups?
AdvancedKubernetes7 min
A NetworkPolicy is applied but pods that should be blocked can still communicate — why might it not be enforced?
AdvancedKubernetes7 min
How would you debug a Service routing failure differently if you were using a service mesh like Istio instead of plain kube-proxy-based Services?
AdvancedKubernetesIstio7 min
You deploy a new version of a Kubernetes Deployment. The pods show Running and pass their readiness checks, but the Service in front of them stops routing traffic entirely. Where do you look?
IntermediateKubernetes10 min
What's the difference between ClusterIP, NodePort, LoadBalancer, and ExternalName, and how do you choose?
BeginnerKubernetes5 min
Why does Kubernetes require a CNI plugin at all — what job does it do that kube-proxy doesn't?
BeginnerKubernetes5 min