Workloads & Scheduling

You are managing a Kubernetes cluster with three worker nodes. A deployment named 'frontend' is configured with 3 replicas. After a node failure, you notice that only 2 pods are running, and the third pod is stuck in 'Pending' state. The remaining nodes have sufficient CPU and memory. You check the deployment events and find no errors. You also verify that the PersistentVolumeClaims (PVCs) used by the deployment are bound. What is the most likely reason the third pod is not scheduled?

A cluster administrator wants to ensure that no pods are scheduled on the master node(s). Which approach is the best practice?

An administrator wants to ensure that a critical Pod always runs on a node that has an SSD. Which approach should be used?

A cluster administrator wants to ensure that a set of batch processing Pods are preemptible and should not cause disruption to other critical workloads. Which combination of scheduling features should be used?

A Kubernetes cluster has a deployment with 3 replicas. After a node failure, you notice that only 2 pods are running, and the deployment has not rescheduled the missing pod. What is the most likely cause?

A Pod with a restartPolicy of 'OnFailure' exits with code 0. What will happen?

You are a platform engineer managing a Kubernetes cluster with 5 worker nodes (node1-node5). The cluster runs a mix of stateless web services and stateful databases. Users report that a critical database Pod (part of a StatefulSet) is frequently evicted during node maintenance. The StatefulSet has a single replica. You need to improve the availability of this database Pod. The current configuration: the Pod has resource requests (2 CPU, 4Gi memory) and limits (4 CPU, 8Gi memory). The cluster uses the default scheduler with no custom policies. Nodes have varying capacities: node1 and node2 have 8 CPU/32Gi memory, node3-node5 have 4 CPU/16Gi memory. During rolling node reboots, the database Pod gets evicted and takes a long time to reschedule because no node has enough resources. What should you do to minimize downtime and ensure the Pod is rescheduled promptly after eviction?

Your team is deploying a new application that consists of a web frontend and a backend API. The frontend must be accessible from outside the cluster, and the backend should only be accessible from within the cluster. The cluster has multiple namespaces: 'frontend' and 'backend'. You have been asked to design the deployment. The frontend Deployment should have 5 replicas, and the backend Deployment should have 3 replicas. Additionally, you need to ensure that the frontend pods can communicate with the backend pods using a stable DNS name. You also want to isolate the backend from other namespaces. Which set of resources should you create?

A Pod is in Pending state for a long time. 'kubectl describe pod' shows the event: '0/3 nodes are available: 3 node(s) had taints that the pod didn't tolerate'. What is the most likely issue?

You are managing a Kubernetes cluster that hosts a microservices application. One of the services, 'payment-processor', is critical and must always be available. It has a Deployment with 3 replicas, each requesting 1 CPU and 2Gi memory. Recently, the team added a new service 'data-analyzer' that runs as a DaemonSet on all nodes, consuming significant CPU and memory. After the addition, you notice that 'payment-processor' pods are occasionally being evicted, and new pods are slow to be scheduled. You check node resource usage and find that some nodes are overcommitted. You want to ensure that 'payment-processor' pods are never evicted and are scheduled before less critical workloads. Which action should you take?

Drag and drop the steps to troubleshoot a Node that is in NotReady state into the correct order.

An operations team must guarantee that exactly one copy of a log-shipping Pod runs on every worker node, including nodes added to the cluster later, and that each node gets at most one such Pod. Some nodes carry the taint 'dedicated=batch:NoSchedule'. Which resource and configuration should the team use?

A company runs a batch job that processes a queue. The job should run to completion exactly once. Which resource should be used?

A developer wants to deploy a pod that will run only once to initialize a database schema. Which Kubernetes resource should they use?

A Pod in a Deployment is CrashLoopBackOff. 'kubectl logs' shows the application exits with code 1 after printing one line. The Pod has a liveness probe that checks an HTTP endpoint. What should be checked first?

A user creates a Deployment with replicas=3. Two Pods are running, but the third is stuck in ContainerCreating. 'kubectl describe pod' shows 'Failed to create pod sandbox: rpc error: code = Unknown desc = failed to create containerd task: OCI runtime create failed: container_linux.go:349: starting container process caused: exec: "/app": stat /app: no such file or directory'. What is the most likely cause?

Which THREE of the following are valid considerations when using resource requests and limits? (Select 3)

You have a StatefulSet with 5 pods, each requiring a unique stable network identity. The StatefulSet is scaled down from 5 to 3. Which pods will be terminated?

A Kubernetes cluster has a node pool with GPU nodes labeled 'accelerator=nvidia-tesla'. A Pod requires a GPU. Which configuration is necessary?

A developer deployed a Pod that is stuck in Pending state. The cluster has one worker node with taint 'node.kubernetes.io/disk-pressure:NoSchedule'. The Pod does not specify any tolerations. What is the most likely cause?