CKA Cluster Architecture 3 — Questions and Answers
Question 1: Which etcd configuration parameter controls how long a follower waits before triggering a leader election?
- --heartbeat-interval
- --election-timeout (Correct answer)
- --snapshot-count
- --max-snapshots
Correct answer: --election-timeout
The --election-timeout parameter defines how long an etcd follower waits without hearing from the leader before starting a new election.
Question 2: In a high-availability control plane setup, what is the recommended minimum number of etcd members?
- 2
- 3 (Correct answer)
- 4
- 5
Correct answer: 3
A 3-member etcd cluster can tolerate the failure of 1 member while maintaining quorum (majority = 2 of 3).
Question 3: What is the role of a cloud-controller-manager in a Kubernetes cluster?
- Manages container image pulls from cloud registries
- Integrates Kubernetes with cloud provider APIs for nodes, routes, and load balancers (Correct answer)
- Schedules Pods on cloud-specific instance types
- Rotates cloud provider credentials stored in Secrets
Correct answer: Integrates Kubernetes with cloud provider APIs for nodes, routes, and load balancers
The cloud-controller-manager runs cloud-specific control loops for node lifecycle, route configuration, and service load balancer provisioning.
Question 4: Which flag on the kube-apiserver controls the list of admission controllers that are enabled?
- --enable-admission-plugins (Correct answer)
- --admission-control
- --runtime-config
- --feature-gates
Correct answer: --enable-admission-plugins
The --enable-admission-plugins flag on the kube-apiserver specifies which admission controllers are active in the admission chain.
Question 5: A static Pod manifest is placed in /etc/kubernetes/manifests/. Which component is responsible for starting that Pod?
- kube-scheduler
- kube-controller-manager
- kubelet (Correct answer)
- kube-apiserver
Correct answer: kubelet
The kubelet watches its static Pod manifest directory and directly creates/manages Pods defined there without going through the scheduler.
Question 6: What is the purpose of the Node Lease object in Kubernetes?
- Reserve IP addresses for new Pods on the node
- Provide a lightweight heartbeat mechanism to reduce load on etcd (Correct answer)
- Coordinate Rolling Updates across nodes
- Enforce resource quotas at the node level
Correct answer: Provide a lightweight heartbeat mechanism to reduce load on etcd
Node Leases are lightweight objects in the kube-node-lease namespace that the kubelet updates frequently as a heartbeat, avoiding heavier Node status updates.
Question 7: Which Kubernetes feature allows the scheduler to be replaced or extended without modifying core Kubernetes code?
- Admission Webhooks
- Scheduler Profiles and Extenders (Correct answer)
- Custom Resource Definitions
- Node Taints
Correct answer: Scheduler Profiles and Extenders
Scheduler Extenders and Scheduler Profiles let you plug in custom scheduling logic or run multiple scheduler configurations without patching core code.
CKA Cluster Architecture 3
Which etcd configuration parameter controls how long a follower waits before triggering a leader election?