Container Orchestration with Kubernetes Questions and Answers for Viva

Answer-1: Kubernetes is an open-source container orchestration platform for automating deployment, scaling, and management of containerized applications.

Answer-2: The main components include the Master Node (API Server, Scheduler, Controller Manager, etcd) and Worker Nodes (Kubelet, Kube-proxy, container runtime).

Answer-3: A Pod is the smallest deployable unit in Kubernetes, which can contain one or more tightly coupled containers.

Answer-4: The API Server acts as the front end of the Kubernetes control plane, handling RESTful requests and updating the cluster state.

Answer-5: etcd is a distributed key-value store used by Kubernetes to store all cluster data and configuration.

Answer-6: The Scheduler assigns Pods to available Nodes based on resource availability, policies, and constraints.

Answer-7: A ReplicaSet ensures that a specified number of Pod replicas are running at any given time.

Answer-8: A Deployment manages ReplicaSets and provides declarative updates and rollback functionality.

Answer-9: Namespaces provide a mechanism to isolate groups of resources within a single Kubernetes cluster.

Answer-10: Services expose Pods to the network and provide load balancing and stable endpoints for Pods.

Answer-11: NodePort, and LoadBalancer service types.

Answer-12: A DaemonSet ensures that a copy of a Pod runs on all or selected nodes.

Answer-13: StatefulSet manages stateful applications with unique network identities and persistent storage.

Answer-14: Using PersistentVolumes (PV) and PersistentVolumeClaims (PVC) to abstract storage provisioning and management.

Answer-15: ConfigMap is an API object used to store non-confidential configuration data in key-value pairs.

Answer-16: Secrets store sensitive data like passwords and tokens, which can be injected into Pods securely.

Answer-17: By updating a Deployment, Kubernetes incrementally replaces old Pods with new ones without downtime.

Answer-18: Ingress manages external access to services, typically HTTP/HTTPS, with routing rules.

Answer-19: Kubelet is an agent that runs on each worker node to ensure containers are running in Pods as expected.

Answer-20: kube-proxy maintains network rules on nodes for service abstraction and load balancing.

Answer-21: By running multiple master nodes and replicating etcd data to prevent a single point of failure.

Answer-22: Labels are key-value pairs attached to objects for identification; selectors filter and select groups of objects based on labels.

Answer-23: HPA automatically scales the number of Pods based on CPU utilization or custom metrics.

Answer-24: By defining resource requests and limits in Pod specifications.

Answer-25: A Job creates one or more Pods to perform a task until completion.

Answer-26: A CronJob runs Jobs on a scheduled time or interval, while a Job runs once until completion.

Answer-27: Taints allow nodes to repel Pods, while tolerations allow Pods to be scheduled on tainted nodes.

Answer-28: The Control Plane manages the cluster state and makes decisions to maintain desired state.

Answer-29: Namespaces isolate resources for multi-tenant environments, resource quotas, and access control.

Answer-30: Using Role-Based Access Control (RBAC), network policies, secrets management, and audit logging.

Answer-31: RBAC controls access to Kubernetes resources based on user roles and permissions.

Answer-32: Deployments manage stateless applications with scalable replicas; DaemonSets run a Pod on every node for cluster-wide services.

Answer-33: It limits voluntary disruptions (e.g., upgrades) to ensure minimum Pod availability.

Answer-34: Through the API Server over secure channels using kubelet and other agents.

Answer-35: The runtime (e.g., Docker, containerd) is responsible for running containers on nodes.

Answer-36: Helm is a package manager for Kubernetes that simplifies deployment and management of applications using Helm charts.

Answer-37: Using tools like Prometheus, Grafana, and Kubernetes Metrics Server.

Answer-38: CRDs extend Kubernetes API to manage custom objects and resources.

Answer-39: Secrets are base64 encoded and can be encrypted at rest with RBAC controlling access.

Answer-40: Init containers run and complete before app containers start; used for setup tasks.

Answer-41: By running two separate environments (blue and green) and switching traffic using services or ingress.

Answer-42: Service mesh provides advanced microservice communication features beyond basic Kubernetes networking.

Answer-43: kubeadm is a CLI tool to bootstrap and configure a Kubernetes cluster easily.

Answer-44: By upgrading master and worker nodes incrementally using kubeadm or managed service tools.

Answer-45: Network policies control traffic flow between Pods based on rules and selectors.

Answer-46: cAdvisor collects resource usage and performance metrics from running containers.

Answer-47: ClusterIP exposes an internal IP; ExternalName maps a service to an external DNS name.

Answer-48: Check Pod logs, describe the Pod, check events, and inspect node status.

Answer-49: Operators extend Kubernetes with domain-specific automation for managing complex applications.

Answer-50: Docker packages and runs containers; Kubernetes orchestrates and manages these containers at scale.