Workloads and Scheduling

A CronJob is configured to run every hour. You notice that the job did not run at the scheduled time. What is the most likely reason?

You are debugging a Pod that is in 'Pending' state. The output of 'kubectl describe pod' shows: Events: Type Reason Age From Message ---- ------ ---- ---- ------- Warning FailedScheduling 2m default-scheduler 0/3 nodes are available: 1 Insufficient cpu, 2 node(s) had taint {node-role.kubernetes.io/master: }, that the pod didn't tolerate. What does this indicate?

You want to run a batch job that processes a queue and then terminates. The job should be run only once. Which Kubernetes resource should you use?

What is the default pod phase when a pod is first created but not yet running?

A CronJob runs every hour. The job takes 45 minutes to complete. What is the default behavior if the next scheduled time occurs while the previous job is still running?

Which annotation is commonly used to trigger a rollout restart of a Deployment when a ConfigMap is updated?

A Deployment named 'web-app' has 5 replicas. You want to perform a rolling update with a maximum of 3 pods unavailable during the update and a maximum of 2 extra pods above the desired count. Which YAML snippet correctly sets the rolling update strategy?

Which THREE are valid ways to inject configuration data into a pod?

You create a ConfigMap named 'app-config' with key 'database.url'. Which command correctly creates a pod that injects this ConfigMap value as an environment variable named 'DB_URL'?

Which command creates a ConfigMap named 'app-config' from a file 'config.properties'?

A pod with priorityClassName: high is pending. You describe the pod and see the event: '0/3 nodes are available: 3 node(s) didn't match pod affinity/anti-affinity, 1 node(s) had taint {node-role.kubernetes.io/control-plane: }, that the pod didn't tolerate.' The pod has required anti-affinity to avoid co-location with pods from the same app. How can you get the pod scheduled?

Which THREE of the following are true about HorizontalPodAutoscaler (HPA)?

A StatefulSet named 'db' has 3 replicas. You need to update the pod template to change the resource limits. After applying the change, you run 'kubectl rollout status sts db' and it hangs. What is the most likely reason?

You have a DaemonSet that runs a logging agent. You want to ensure it only runs on nodes with GPU. Which field should you set in the DaemonSet's pod template spec?

Which TWO of the following are valid ways to expose environment variables from a ConfigMap to a pod? (Select TWO.)

You want to ensure that a pod only runs on nodes that have a GPU. Nodes with GPUs are labeled with 'gpu=true'. Which scheduling constraint should you use?

A pod has resource requests: cpu: 250m, memory: 128Mi. The node has 2 CPU cores and 4Gi memory. What is the maximum number of such pods that can fit on this node based solely on CPU requests?

Which command creates a Job that runs a single pod to execute the command 'echo Hello'?

A Pod is stuck in 'Pending' state. You run 'kubectl describe pod my-pod' and see the event: '0/3 nodes are available: 1 node(s) had taint {node-role.kubernetes.io/master: }, that the pod didn't tolerate, 2 Insufficient cpu.' The pod has resource requests: cpu: 2, memory: 1Gi. The cluster has 3 nodes: one control-plane with taint node-role.kubernetes.io/master:NoSchedule, and two worker nodes each with 1 CPU. What is the most likely cause?

A pod is in 'Pending' state. 'kubectl describe pod' shows '0/4 nodes are available: 1 node(s) had taint that the pod didn't tolerate, 2 node(s) didn't match pod's node affinity/selector, 1 node(s) had insufficient memory'. What does this indicate?

Which TWO statements are correct regarding DaemonSets?

A pod in the 'production' namespace is in a CrashLoopBackOff state. The pod has been running successfully for several days. You run 'kubectl describe pod app-pod -n production' and see the message: 'OOMKilled'. What is the MOST appropriate action to resolve this issue?

A Pod has an init container that writes a configuration file, and the main container reads that file. The init container runs successfully, but the main container fails with 'file not found'. What is the most likely cause?

You create a PriorityClass named 'high-priority' with value 1000000 (one million). A pod uses this PriorityClass. The cluster has limited resources. What scheduling behavior is most likely?

What is the purpose of a PriorityClass in Kubernetes?

You have a Deployment named 'web-app' in the 'default' namespace. You run the following command: kubectl rollout history deployment web-app. The output shows: revision 1, revision 2, revision 3. You want to roll back to revision 1. Which command achieves this?

You have a Deployment 'db' with 3 replicas. Each pod writes to a PersistentVolumeClaim (PVC). A StatefulSet is required for stable network identities and ordered pod management. Which of the following is a key characteristic that differentiates a StatefulSet from a Deployment?

Which command creates a ConfigMap named 'app-config' from the file 'config.properties'?

Which TWO of the following are valid ways to specify resource requests and limits for a container in a pod? (Select 2)

Which kubectl command will show the rollout history of a Deployment named 'web-app'?

You have a ResourceQuota in a namespace that sets limits: pods: 10, requests.cpu: 4, requests.memory: 8Gi. You try to create a Pod with requests.cpu: 1, requests.memory: 2Gi, and no limits. The namespace currently has 8 pods using 3 CPUs and 5Gi memory in total requests. What happens?

Which THREE of the following are valid ways to restrict or influence pod scheduling using taints and tolerations? (Select THREE.)

A StatefulSet named 'web' has 3 replicas. You need to update the container image from 'nginx:1.19' to 'nginx:1.20' using a rolling update with ordered pod management. What must you ensure in the StatefulSet spec?

A pod with an init container that runs a database migration fails. The init container exits with code 1. What is the pod's status?

You have a PriorityClass 'high-priority' with value 1000 and 'low-priority' with value 100. A pod A with 'high-priority' is pending because the node has no resources. A pod B with 'low-priority' is running on that node. What will happen if preemption is enabled?

A DaemonSet named 'fluentd' is configured to run on all nodes. After adding a new node to the cluster, you notice that the DaemonSet pod is not running on the new node. What could be the cause?

A pod with a resource request of 500m CPU and a limit of 1 CPU is scheduled. The node has a CPU capacity of 2 cores. What does the '500m' represent?

Which two statements about HorizontalPodAutoscaler (HPA) are correct?

A Deployment named 'app' has 3 replicas. The rolling update strategy is set with maxSurge=1 and maxUnavailable=1. During an update, a new ReplicaSet is created. How many pods will be in terminating state at the moment when the new ReplicaSet has 2 pods ready?