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Compare image digest, registry manifest, Pod imageID, rollout timestamp and supply-chain approval. This step belongs to Immutable container images and digests rather than the complementary implementation and evidence pair. The intended approach is: Keep etcd highly available and maintain secure, tested snapshots of Kubernetes API state rather than treating it as ordinary container storage. Validate with: Inspect etcd quorum health, member status, snapshot freshness, certificate validity and restore procedure. Workload context: An operator removes two members from a three-member etcd cluster without calculating the quorum needed to accept writes.

The container sees the intended isolated resources while usage limits are reflected in host accounting. This step belongs to Linux namespaces and cgroups rather than the complementary implementation and evidence pair. The intended approach is: Keep etcd highly available and maintain secure, tested snapshots of Kubernetes API state rather than treating it as ordinary container storage. Validate with: Inspect etcd quorum health, member status, snapshot freshness, certificate validity and restore procedure. Workload context: An operator removes two members from a three-member etcd cluster without calculating the quorum needed to accept writes.

Use namespaces to group namespaced resources and policies, and add explicit RBAC and network controls for isolation. This step belongs to Namespace scope and limits rather than the complementary implementation and evidence pair. The intended approach is: Keep etcd highly available and maintain secure, tested snapshots of Kubernetes API state rather than treating it as ordinary container storage. Validate with: Inspect etcd quorum health, member status, snapshot freshness, certificate validity and restore procedure. Workload context: An operator removes two members from a three-member etcd cluster without calculating the quorum needed to accept writes.

Pods on different eligible nodes communicate according to network design and report working network addresses. This step belongs to CNI Pod networking implementation rather than the complementary implementation and evidence pair. The intended approach is: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Validate with: Examine authentication identity, RBAC decision, admission webhook result and API response status. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

Inspect securityContext, runAsUser, allowPrivilegeEscalation, capabilities, seccompProfile and startup errors. This step belongs to Linux securityContext and seccomp basics rather than the complementary implementation and evidence pair. The intended approach is: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Validate with: Examine authentication identity, RBAC decision, admission webhook result and API response status. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

Require approved registry artifacts and verifiable signatures or digests before admitting production workloads. This step belongs to Image provenance and admission policies rather than the complementary implementation and evidence pair. The intended approach is: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Validate with: Examine authentication identity, RBAC decision, admission webhook result and API response status. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

Assign readiness for traffic acceptance, liveness for unhealthy restarts and startup for slow initialization when appropriate. This action addresses Readiness liveness and startup probe behavior instead of the controlling requirement. Readiness failure removes a Pod from ready endpoints; liveness failure may restart a container. For this scenario prefer: Configure a supported StorageClass and CSI provisioner to dynamically create backing volumes for PVCs. Workload context: An engineer expects setting storageClassName on a claim to create usable storage even when the provisioner controller is unavailable.

Diagnose image-pull problems by validating image reference, registry availability, permissions and Secret scope. This action addresses ImagePullBackOff registry and auth errors instead of the controlling requirement. ImagePullBackOff is a retrieval or authorization problem; changing app readiness probes cannot fix a missing image. For this scenario prefer: Configure a supported StorageClass and CSI provisioner to dynamically create backing volumes for PVCs. Workload context: An engineer expects setting storageClassName on a claim to create usable storage even when the provisioner controller is unavailable.

Use emptyDir for temporary Pod-scoped data and PVC-backed volumes when data must survive Pod replacement. This action addresses Ephemeral emptyDir versus persistent volumes instead of the controlling requirement. emptyDir exists for the lifetime of a Pod on a node and is lost when the Pod is removed. For this scenario prefer: Configure a supported StorageClass and CSI provisioner to dynamically create backing volumes for PVCs. Workload context: An engineer expects setting storageClassName on a claim to create usable storage even when the provisioner controller is unavailable.

Inspect service ownership, API contract, timeout/retry behavior, communication coupling and failure domains. These observations are more relevant to Microservices contracts and failure isolation, not this case. The distinguishing check is: Identify each project role, integration point, maintainer documentation and whether it belongs to Kubernetes core. Workload context: A new platform team chooses a service mesh to manage service-to-service traffic but believes it replaces Kubernetes scheduling and etcd.

Review security policy, affected version, maintainer contact, severity evidence and coordinated disclosure plan. These observations are more relevant to Responsible vulnerability disclosure in communities, not this case. The distinguishing check is: Identify each project role, integration point, maintainer documentation and whether it belongs to Kubernetes core. Workload context: A new platform team chooses a service mesh to manage service-to-service traffic but believes it replaces Kubernetes scheduling and etcd.

Inspect manifests for proprietary resources, storage/network API dependencies, image compatibility and migration cost. These observations are more relevant to Open standards vendor-neutral portability, not this case. The distinguishing check is: Identify each project role, integration point, maintainer documentation and whether it belongs to Kubernetes core. Workload context: A new platform team chooses a service mesh to manage service-to-service traffic but believes it replaces Kubernetes scheduling and etcd.

Check Pod priority, preemptionPolicy, scheduling events, available alternatives and victim selection. These observations are more relevant to PriorityClass and preemption, not this case. The distinguishing check is: Check node unschedulable state, PodDisruptionBudgets, DaemonSets, local storage and eviction events. Workload context: A platform team drains a node hosting local ephemeral data without evaluating whether eviction will discard required state.

Inspect DaemonSet desired/current/ready counts, node eligibility, tolerations and per-node Pod placement. These observations are more relevant to DaemonSet node-local workloads, not this case. The distinguishing check is: Check node unschedulable state, PodDisruptionBudgets, DaemonSets, local storage and eviction events. Workload context: A platform team drains a node hosting local ephemeral data without evaluating whether eviction will discard required state.

Check server and kubelet versions, deprecated APIs, CNI/CSI compatibility, maintenance order and rollback limits. These observations are more relevant to Kubernetes upgrades and version skew, not this case. The distinguishing check is: Check node unschedulable state, PodDisruptionBudgets, DaemonSets, local storage and eviction events. Workload context: A platform team drains a node hosting local ephemeral data without evaluating whether eviction will discard required state.

Examine authentication identity, RBAC decision, admission webhook result and API response status. These observations are more relevant to Authentication authorization and admission order, not this case. The distinguishing check is: Review storageClass volumeBindingMode, PVC condition, Pod node constraints and CSI topology events. Workload context: A PVC stays Pending while no Pod references it and the team calls the CSI provisioner broken despite WaitForFirstConsumer.

Inspect PV persistentVolumeReclaimPolicy, underlying disk state, claim release and storage provisioner behavior. These observations are more relevant to PV reclaim policy Retain versus Delete, not this case. The distinguishing check is: Review storageClass volumeBindingMode, PVC condition, Pod node constraints and CSI topology events. Workload context: A PVC stays Pending while no Pod references it and the team calls the CSI provisioner broken despite WaitForFirstConsumer.

Inspect PVC phase, PV claimRef, capacity, accessModes, storageClassName and volume-mount events. These observations are more relevant to PersistentVolume and claim bindings, not this case. The distinguishing check is: Review storageClass volumeBindingMode, PVC condition, Pod node constraints and CSI topology events. Workload context: A PVC stays Pending while no Pod references it and the team calls the CSI provisioner broken despite WaitForFirstConsumer.

Principals can perform only intended operations at the correct scope while denied actions remain inaccessible. That result validates Role and ClusterRole authorization rather than the requirement here. Verify instead: Control-plane and node upgrades complete within supported skew with workload compatibility checks passing. Workload context: A team upgrades workers two minor versions ahead of an older API server without consulting supported skew policy.

Pending eligible Pods receive appropriate node bindings when capacity and constraints allow scheduling. That result validates Scheduler responsibility and binding rather than the requirement here. Verify instead: Control-plane and node upgrades complete within supported skew with workload compatibility checks passing. Workload context: A team upgrades workers two minor versions ahead of an older API server without consulting supported skew policy.

Operators identify the failing object and use evidence before editing controllers or escalating access. That result validates kubectl inspect and describe diagnostics rather than the requirement here. Verify instead: Control-plane and node upgrades complete within supported skew with workload compatibility checks passing. Workload context: A team upgrades workers two minor versions ahead of an older API server without consulting supported skew policy.

Platform selections fit the actual problem without expecting one component to implement the whole cloud native stack. That result validates CNCF ecosystem and Kubernetes roles rather than the requirement here. Verify instead: A single downstream failure degrades gracefully without causing an uncontrolled cascade across independent services. Workload context: A product team adds bounded retries yet creates duplicate orders because its operation lacks idempotency and side-effect controls.

Metrics are collected from intended targets at expected intervals with bounded label series and useful alerts. That result validates Prometheus pull scraping and metrics endpoints rather than the requirement here. Verify instead: A single downstream failure degrades gracefully without causing an uncontrolled cascade across independent services. Workload context: A product team adds bounded retries yet creates duplicate orders because its operation lacks idempotency and side-effect controls.

Workloads can be redeployed between supported clusters with explicitly identified environment-specific adaptations. That result validates Open standards vendor-neutral portability rather than the requirement here. Verify instead: A single downstream failure degrades gracefully without causing an uncontrolled cascade across independent services. Workload context: A product team adds bounded retries yet creates duplicate orders because its operation lacks idempotency and side-effect controls.

Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. This action addresses Authentication authorization and admission order instead of the controlling requirement. Authentication answers who called, authorization answers what may be done, and admission can apply policy to allowed requests. For this scenario prefer: Configure Pod Security Admission policy levels for namespaces to restrict unsafe Pod settings while documenting exceptions. Workload context: A cluster upgrade changes workload securityContext defaults and the team ignores admission warning logs during staging.

Combine RBAC with NetworkPolicy to control both Kubernetes API permissions and east-west workload traffic. This action addresses Namespace segmentation with NetworkPolicies instead of the controlling requirement. NetworkPolicy governs data-plane traffic, whereas RBAC governs API actions; neither alone replaces the other. For this scenario prefer: Configure Pod Security Admission policy levels for namespaces to restrict unsafe Pod settings while documenting exceptions. Workload context: A cluster upgrade changes workload securityContext defaults and the team ignores admission warning logs during staging.

Use CoreDNS or the configured cluster DNS service to resolve Service and Pod naming in their correct namespaces. This action addresses Cluster DNS and service discovery instead of the controlling requirement. Kubernetes DNS uses namespace-aware search paths; a fully qualified Service name avoids ambiguity across namespaces. For this scenario prefer: Configure Pod Security Admission policy levels for namespaces to restrict unsafe Pod settings while documenting exceptions. Workload context: A cluster upgrade changes workload securityContext defaults and the team ignores admission warning logs during staging.

Use kube-apiserver as the authenticated front end for Kubernetes API objects, rather than connecting clients directly to etcd. This action addresses Kubernetes API server and API requests instead of the controlling requirement. kube-apiserver validates and serves API requests; etcd stores cluster state rather than exposing the user API. For this scenario prefer: Assign stable labels for matching workload membership, and use annotations for nonselecting descriptive metadata. Workload context: A Service routes to no endpoints after a release because app labels change but its selector retains the old key.

Use namespaces to group namespaced resources and policies, and add explicit RBAC and network controls for isolation. This action addresses Namespace scope and limits instead of the controlling requirement. Namespaces organize resource names but are not automatically strong security boundaries or separate clusters. For this scenario prefer: Assign stable labels for matching workload membership, and use annotations for nonselecting descriptive metadata. Workload context: A Service routes to no endpoints after a release because app labels change but its selector retains the old key.

Use a DaemonSet to run a supported node agent across eligible nodes, respecting taints and selectors. This action addresses DaemonSet node-local workloads instead of the controlling requirement. A DaemonSet creates node-level replicas automatically rather than a fixed overall replica count like a Deployment. For this scenario prefer: Assign stable labels for matching workload membership, and use annotations for nonselecting descriptive metadata. Workload context: A Service routes to no endpoints after a release because app labels change but its selector retains the old key.

Report suspected project security vulnerabilities through the designated private security channel before public reproduction details or exploit examples. This action addresses Responsible vulnerability disclosure in communities instead of the controlling requirement. Public bug trackers are not always the right venue for undisclosed security issues; project security policies define channels. For this scenario prefer: Follow Kubernetes Special Interest Group ownership and enhancement processes when proposing changes to core functionality. Workload context: A company wants to understand which Kubernetes SIG owns a networking proposal and how contributors discuss compatibility concerns.

Check a project's license, contributor requirements and redistribution obligations before copying or shipping components. This action addresses Open source licensing and contribution basics instead of the controlling requirement. Open source permits work under a specific license; public availability of source code alone does not erase conditions. For this scenario prefer: Follow Kubernetes Special Interest Group ownership and enhancement processes when proposing changes to core functionality. Workload context: A company wants to understand which Kubernetes SIG owns a networking proposal and how contributors discuss compatibility concerns.

Choose metrics for measurements over time, logs for detailed events and traces for end-to-end request execution analysis. This action addresses Metrics logs and traces distinctions instead of the controlling requirement. Logs, metrics and traces answer different questions; observability requires instrumenting and interpreting their context. For this scenario prefer: Follow Kubernetes Special Interest Group ownership and enhancement processes when proposing changes to core functionality. Workload context: A company wants to understand which Kubernetes SIG owns a networking proposal and how contributors discuss compatibility concerns.