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Only reviewed images with accepted risk enter production and later findings can be traced to deployed digests. That result validates Image scanning and software bills of materials rather than the requirement here. Verify instead: The selected isolation model meets workload portability and security needs without claiming that containers include separate guest kernels. Workload context: An engineer chooses a full VM for each tiny stateless process without considering container density or operational requirements.

The container sees the intended isolated resources while usage limits are reflected in host accounting. That result validates Linux namespaces and cgroups rather than the requirement here. Verify instead: The selected isolation model meets workload portability and security needs without claiming that containers include separate guest kernels. Workload context: An engineer chooses a full VM for each tiny stateless process without considering container density or operational requirements.

Replicas spread or co-locate according to declared constraints with predictable behavior when no feasible topology exists. That result validates Pod affinity anti-affinity rather than the requirement here. Verify instead: The selected isolation model meets workload portability and security needs without claiming that containers include separate guest kernels. Workload context: An engineer chooses a full VM for each tiny stateless process without considering container density or operational requirements.

Run containers with nonroot identities, minimal capabilities and an appropriate seccomp profile for reduced kernel attack surface. This action addresses Linux securityContext and seccomp basics instead of the controlling requirement. Disabling privilege escalation and dropping Linux capabilities reduce risk but do not replace image or API authorization. For this scenario prefer: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

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: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

Diagnose memory limit terminations using lastState and observed working-set growth rather than assuming every restart is application logic. This action addresses Container OOMKilled and resource pressure instead of the controlling requirement. Container memory exceeding its cgroup limit can trigger OOMKilled even when node aggregate memory seems available. For this scenario prefer: Distinguish authenticating a Kubernetes API caller from authorizing verbs and validating or mutating admission behavior. Workload context: A client receives 401 after presenting an expired token, and the operator attempts to fix it by granting cluster-admin rights.

Evaluate CNCF sandbox, incubating and graduated projects in context of maintenance, community adoption and technical fit. This action addresses CNCF project maturity and adoption decisions instead of the controlling requirement. CNCF maturity levels indicate aspects of governance and adoption, not a guarantee of security or perfect product fit. For this scenario prefer: Prefer open APIs, OCI images and Kubernetes-compatible deployment contracts where portability matters while accounting for provider-specific extensions. Workload context: A vendor migration promises zero changes even though the workloads depend on cloud-specific identity and networking controllers.

Define user-relevant service-level indicators and objectives for availability, error rate or latency with practical alert thresholds. This action addresses SLIs SLOs and golden signals instead of the controlling requirement. An SLI is a measurement, an SLO is a target and an SLA is a contractual commitment; they should not be conflated. For this scenario prefer: Prefer open APIs, OCI images and Kubernetes-compatible deployment contracts where portability matters while accounting for provider-specific extensions. Workload context: A vendor migration promises zero changes even though the workloads depend on cloud-specific identity and networking controllers.

Expose application metrics in supported Prometheus format and configure authorized scrape targets and label cardinality. This action addresses Prometheus pull scraping and metrics endpoints instead of the controlling requirement. Prometheus primarily scrapes targets on an interval; instrumentation must expose values and high-cardinality labels can overload storage. For this scenario prefer: Prefer open APIs, OCI images and Kubernetes-compatible deployment contracts where portability matters while accounting for provider-specific extensions. Workload context: A vendor migration promises zero changes even though the workloads depend on cloud-specific identity and networking controllers.

Configure StorageClass WaitForFirstConsumer when scheduling topology must influence dynamic volume provisioning. This action addresses WaitForFirstConsumer volume binding instead of the controlling requirement. A PVC may legitimately remain unbound until a Pod consumes it under WaitForFirstConsumer. For this scenario prefer: Choose PV access modes based on how nodes and workloads must mount storage and verify CSI driver capability. Workload context: Two replicas on different worker nodes need to edit shared files but the selected volume supports only ReadWriteOnce.

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: Choose PV access modes based on how nodes and workloads must mount storage and verify CSI driver capability. Workload context: Two replicas on different worker nodes need to edit shared files but the selected volume supports only ReadWriteOnce.

Configure Pod Security Admission policy levels for namespaces to restrict unsafe Pod settings while documenting exceptions. This action addresses Pod Security Admission and namespaces instead of the controlling requirement. Pod Security Admission evaluates security standards at admission; it does not continuously sandbox existing containers after admission. For this scenario prefer: Choose PV access modes based on how nodes and workloads must mount storage and verify CSI driver capability. Workload context: Two replicas on different worker nodes need to edit shared files but the selected volume supports only ReadWriteOnce.

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: Use ClusterIP for private service access and NodePort only when node-level external ports are intentionally needed. Workload context: A private backend only used by Pods is exposed through NodePort and the security team finds the node port reachable outside the cluster.

Use a Service type LoadBalancer with a supported cloud or in-cluster load-balancer controller to provide an approved external endpoint. This action addresses LoadBalancer Service provisioning instead of the controlling requirement. A LoadBalancer Service depends on an implementation or provider controller; creating it does not guarantee an external address. For this scenario prefer: Use ClusterIP for private service access and NodePort only when node-level external ports are intentionally needed. Workload context: A private backend only used by Pods is exposed through NodePort and the security team finds the node port reachable outside the cluster.

Choose PV access modes based on how nodes and workloads must mount storage and verify CSI driver capability. This action addresses ReadWriteOnce and ReadWriteMany semantics instead of the controlling requirement. ReadWriteOnce normally limits read-write mounting to one node, not necessarily exactly one Pod; driver behavior matters. For this scenario prefer: Use ClusterIP for private service access and NodePort only when node-level external ports are intentionally needed. Workload context: A private backend only used by Pods is exposed through NodePort and the security team finds the node port reachable outside the cluster.

Workloads relocate where permitted and the maintained node returns to service without unexpected data loss. That result validates Node cordon drain maintenance rather than the requirement here. Verify instead: Pods assigned to a healthy node start and report status with failed containers surfaced for diagnosis. Workload context: An engineer troubleshoots image start failures by restarting the scheduler despite a healthy node binding and failing runtime socket.

Clients reach the intended healthy backends through a stable Service name despite Pod replacement. That result validates Service stable virtual endpoint rather than the requirement here. Verify instead: Pods assigned to a healthy node start and report status with failed containers surfaced for diagnosis. Workload context: An engineer troubleshoots image start failures by restarting the scheduler despite a healthy node binding and failing runtime socket.

Authorized clients create or read resources through the API and unauthorized calls fail consistently. That result validates Kubernetes API server and API requests rather than the requirement here. Verify instead: Pods assigned to a healthy node start and report status with failed containers surfaced for diagnosis. Workload context: An engineer troubleshoots image start failures by restarting the scheduler despite a healthy node binding and failing runtime socket.

Inspect image metadata, Pod command/args, process exit code and startup logs. These observations are more relevant to Container command entrypoint and arguments, not this case. The distinguishing check is: Inspect Pod label selectors, namespaces, topologyKey and actual placement of matching peer Pods. Workload context: A cache should run near a matching API Pod but its required affinity selector refers to a label no API Pods carry.

Review topology key labels, eligible domains, maxSkew, labelSelector and DoNotSchedule versus ScheduleAnyway. These observations are more relevant to Topology spread constraints, not this case. The distinguishing check is: Inspect Pod label selectors, namespaces, topologyKey and actual placement of matching peer Pods. Workload context: A cache should run near a matching API Pod but its required affinity selector refers to a label no API Pods carry.

Inspect PVC status, volume nodeAffinity, StorageClass volumeBindingMode and node/zone eligibility. These observations are more relevant to PersistentVolume zone binding and placement, not this case. The distinguishing check is: Inspect Pod label selectors, namespaces, topologyKey and actual placement of matching peer Pods. Workload context: A cache should run near a matching API Pod but its required affinity selector refers to a label no API Pods carry.

Check resource namespace, role bindings, quotas and effective network enforcement across namespaces. These observations are more relevant to Namespace scope and limits, not this case. The distinguishing check is: Inspect DaemonSet desired/current/ready counts, node eligibility, tolerations and per-node Pod placement. Workload context: A logging team sets a DaemonSet replica count to three expecting exactly three agents across twenty workers.

Inspect quota hard/used counters, LimitRange defaults and API admission rejection messages. These observations are more relevant to ResourceQuota and LimitRange policies, not this case. The distinguishing check is: Inspect DaemonSet desired/current/ready counts, node eligibility, tolerations and per-node Pod placement. Workload context: A logging team sets a DaemonSet replica count to three expecting exactly three agents across twenty workers.

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: Inspect DaemonSet desired/current/ready counts, node eligibility, tolerations and per-node Pod placement. Workload context: A logging team sets a DaemonSet replica count to three expecting exactly three agents across twenty workers.

Configure StorageClass WaitForFirstConsumer when scheduling topology must influence dynamic volume provisioning. This step belongs to WaitForFirstConsumer volume binding rather than the complementary implementation and evidence pair. The intended approach is: Use emptyDir for temporary Pod-scoped data and PVC-backed volumes when data must survive Pod replacement. Validate with: Inspect volume type, mount paths, Pod owner, node placement and data recovery requirements. Workload context: Two containers inside one Pod share an emptyDir for generated configuration, but a second Pod cannot see it by default.

Inspect PV persistentVolumeReclaimPolicy, underlying disk state, claim release and storage provisioner behavior. This step belongs to PV reclaim policy Retain versus Delete rather than the complementary implementation and evidence pair. The intended approach is: Use emptyDir for temporary Pod-scoped data and PVC-backed volumes when data must survive Pod replacement. Validate with: Inspect volume type, mount paths, Pod owner, node placement and data recovery requirements. Workload context: Two containers inside one Pod share an emptyDir for generated configuration, but a second Pod cannot see it by default.

Resource pressure is resolved without sustained involuntary eviction or unsafe removal of application persistent data. This step belongs to Node pressure and Pod eviction analysis rather than the complementary implementation and evidence pair. The intended approach is: Use emptyDir for temporary Pod-scoped data and PVC-backed volumes when data must survive Pod replacement. Validate with: Inspect volume type, mount paths, Pod owner, node placement and data recovery requirements. Workload context: Two containers inside one Pod share an emptyDir for generated configuration, but a second Pod cannot see it by default.

Teams receive predictable defaults and cannot consume more namespace resources than policy permits. That result validates ResourceQuota and LimitRange policies rather than the requirement here. Verify instead: Pods schedule based on requests and stay within resource policy without avoidable throttling or memory termination. Workload context: A team sets a very low CPU limit and sees high throttling despite spare cluster capacity.

Each eligible node runs the intended agent and newly added eligible nodes receive it automatically. That result validates DaemonSet node-local workloads rather than the requirement here. Verify instead: Pods schedule based on requests and stay within resource policy without avoidable throttling or memory termination. Workload context: A team sets a very low CPU limit and sees high throttling despite spare cluster capacity.

The Pod schedules only onto eligible labeled nodes while other nodes remain untouched. That result validates nodeSelector equality placement rather than the requirement here. Verify instead: Pods schedule based on requests and stay within resource policy without avoidable throttling or memory termination. Workload context: A team sets a very low CPU limit and sees high throttling despite spare cluster capacity.

Inspect PVC phase, PV claimRef, capacity, accessModes, storageClassName and volume-mount events. This step belongs to PersistentVolume and claim bindings rather than the complementary implementation and evidence pair. The intended approach is: Run containers with nonroot identities, minimal capabilities and an appropriate seccomp profile for reduced kernel attack surface. Validate with: Inspect securityContext, runAsUser, allowPrivilegeEscalation, capabilities, seccompProfile and startup errors. Workload context: A team specifies a restrictive seccomp profile but its runtime ignores an unsupported profile name and administrators must check enforcement.

Combine RBAC with NetworkPolicy to control both Kubernetes API permissions and east-west workload traffic. This step belongs to Namespace segmentation with NetworkPolicies rather than the complementary implementation and evidence pair. The intended approach is: Run containers with nonroot identities, minimal capabilities and an appropriate seccomp profile for reduced kernel attack surface. Validate with: Inspect securityContext, runAsUser, allowPrivilegeEscalation, capabilities, seccompProfile and startup errors. Workload context: A team specifies a restrictive seccomp profile but its runtime ignores an unsupported profile name and administrators must check enforcement.

Only approved Pod flows pass and disallowed lateral or outbound connections fail reproducibly. This step belongs to NetworkPolicy ingress egress isolation rather than the complementary implementation and evidence pair. The intended approach is: Run containers with nonroot identities, minimal capabilities and an appropriate seccomp profile for reduced kernel attack surface. Validate with: Inspect securityContext, runAsUser, allowPrivilegeEscalation, capabilities, seccompProfile and startup errors. Workload context: A team specifies a restrictive seccomp profile but its runtime ignores an unsupported profile name and administrators must check enforcement.