GettingStartedWithK8S

Question 1

What is Kubernetes?

Answer 1

Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services that facilitates both declarative configuration and automation.

A tool that helps us manage containers.

Question 2

What does “K8s” mean?

Answer 2

A short way of writing the word “Kubernetes.”

The “8” in “K8s” stands for the eight letters between the “K” and the “s” in the word “Kubernetes.”

Question 3

What does Kubernetes do?

Answer 3

Builds a layer of abstraction around running containers on multiple servers, called the K8s cluster. It manages running the containers on multiple servers in the K8s cluster.

Question 4

Name some K8s Features

Answer 4

1. Container Orchestration
2. Application Reliability
3. Automation

Question 5

Define K8s Container Orchestration

Answer 5

The primary purpose of Kubernetes is to dynamically manage containers across multiple host systems.

Question 6

Define K8s Application Reliability

Answer 6

Kubernetes makes it easier to build reliable, self-healing, and scalable applications.

Question 7

Define K8s Automation

Answer 7

Kubernetes offers a variety of features to help automate the management of your container apps.

Question 8

What are the components of the K8s Architectural Overview?

Answer 8

1. K8s Control Plane
2. K8s Nodes
3. K8s Cluster

Question 9

What is the K8s Control Plane?

Answer 9

The K8s control plane is a collection of multiple components responsible for managing the K8s cluster itself globally. Essentially, the control plane controls the cluster.

Individual control plane components can run on any machine in the cluster but usually run on dedicated controller machines.

Question 10

What is the kube-api-server?

Answer 10

kube-api-server serves the Kubernetes API, the primary frontend interface to the control plane and the cluster itself.

When interacting with your Kubernetes cluster, you will usually do so using the K8s API.

Question 11

Name the 5 components that make up the Kubernetes Control Plane.

Answer 11

1. kube-api-server
2. Etcd
3. kube-controller-manager
4. kube-scheduler
5. cloud-controller-manager

Question 12

What is Etcd?

Answer 12

Etcd is the backend data store for the Kubernetes cluster. It provides high-availability storage for all data relating to the state of the cluster.

Question 13

What is the kube-scheduler?

Answer 13

kube-scheduler handles scheduling, the process of selecting an available node in the cluster on which to run containers. Essentially, the kube-scheduler assigns containers to specific worker nodes.

Question 14

What is the kube-controller-manager?

Answer 14

kube-controller-manager runs a collection of multiple controller utilities in a single process. These controllers carry out a variety of automation-related tasks within the Kubernetes cluster.

Question 15

What is the cloud-controller-manager?

Answer 15

cloud-controller-manager provides an interface between Kubernetes and various cloud platforms. It is only used when using cloud-based resources alongside Kubernetes.

Question 16

What are Kubernetes Nodes?

Answer 16

Kubernetes nodes are the machines where the containers managed by the cluster run. A cluster can have any number of nodes.

Various node components manage containers on he machine and communicate with the K8s control plane.

Question 17

Name the components of a Kubernetes Node.

Answer 17

1. Kublet
2. Container runtime
3. kube-proxy

Question 18

What is the K8s kublet?

Answer 18

Kubelet is the Kubernetes agent that runs on each node. It communicates with the control plane and ensures that the containers are run on its node as instructed by the control plane.

Kublet also handles the process of reporting container status and other data about containers back to the control plane.

Question 19

What is a container runtime?

Answer 19

The container runtime is not built into Kubernetes. It is a separate piece of software that is responsible for actually running containers on the machine.

Kubernetes supports multiple container runtime implementations. Some popular container runtimes are Docker and containerd.

Question 20

What is the kube-proxy?

Answer 20

kube-proxy is a network proxy. It runs on each node and handles some tasks related to providing networking between containers and services in the cluster.

Question 21

What is kubeadm?

Answer 21

A tool to simplify setting up a K8s cluster.

Question 22

What is a Namespace?

Answer 22

Namespaces are virtual clusters backed by the same physical cluster. Kubernetes objects, such as pods and containers, live in namespaces. Namespaces are a way to separate and organize objects in your cluster.

Question 23

What command would you run to list existing namespaces?

Answer 23

kubectl get namespaces

Question 24

What is the name of the namespace that all clusters have?

Answer 24

default

The “default” namespace is used when no other namespace is specified.

Question 25

What is the name of the namespace automatically created by kubeadm?

Answer 25

kube-system The "kube-system" namespace contains or is used for system components.

Question 26

How do you specify a particular namespace when using the kubectl command?

Answer 26

When using the kubectl command, a specific namespace can be specified by using the "--namespace" flag. i.e. kubectl get pods --namespace my-namespace

Question 27

Which namespace is used when no namespace is specified in kubectl commands?

Answer 27

The "default" namespace.

Question 28

How do you create a namespace?

Answer 28

kubectl create namespace my-namespace

Question 29

What command is used to see the pods in the kube-system namespace?

Answer 29

kubectl get pods --namespace kube-system

Question 30

What command is used to list pods in all namespaces?

Answer 30

kubectl get pods --all-namespaces

Question 31

What command would you use to find the namespace of a particular pod?

Answer 31

kubectl get pods --all-namespaces Listing pods for all namespaces using the "--all-namespaces" flag to the "get pods" kubectl command would provide a list of all pod names in all namespaces that you can then traverse to find out which namespace contained a particular pod.

Question 32

What is a namespace? (Choose one) 1. An optional label which helps organize Kubernetes objects. 2. A mechanism for isolating groups of resources within a single cluster. 3. The unique name given to a Pod. 4. A name designating a specific physical cluster.

Answer 32

2. A mechanism for isolating groups of resources within a single cluster.

Question 33

Which flags allow you to specify which Namespace you want to interact with when using kubectl? (Choose 2) 1. --namespace 2. -m 3. --name 4. -n

Answer 33

1. --namespace 4. -n

Question 34

What does kubeadm do? 1. Simplifies the process of building Kubernetes clusters. 2. Simplifies the process of creating Pods. 3. Change cluster configuration. 4. Provides a command-line interface for the Kubernetes API.

Answer 34

1. Simplifies the process of building Kubernetes clusters.

Question 35

What is the primary feature of Kubernetes? 1. Virtualization 2. Container image management 3. Automated Server Provisioning 4. Container Orchestration

Answer 35

4. Container Orchestration

Question 36

Which flag can you use with kubeadm to supply a custom configuration file? 1. --config 2. --config-location 3. --file 4. --config.yml

Answer 36

1. --config

Question 37

What does the 8 in k8s stand for? 1. The maximum number of servers in a cluster. 2. The 8 letters between K and S in Kubernetes. 3. The minimum number of servers in a cluster. 4. The year Kubernetes was first released.

Answer 37

2. The 8 letters between K and S in Kubernetes.

Question 38

What is the Kubernetes control plane? 1. A collection of components that manage the cluster globally. 2. The agent that manages containers on a node. 3. The primary Kubernetes interface. 4. The application that decides which node to run a container on.

Answer 38

1. A collection of components that manage the cluster globally.

Question 39

What is a Namespace? 1. The unique name given to a Pod. 2. An optional label which helps organize Kubernetes objects. 3. A mechanism for isolating groups of resources within a single cluster. 4. A name designating a specific physical cluster.

Answer 39

3. A mechanism for isolating groups of resources within a single cluster.

Question 40

In Kubernetes, what is a Namespace?

Answer 40

In Kubernetes, a namespace provides a mechanism for isolating groups of resources within a single cluster.

Question 41

In Kubernetes, names of resources need to be unique across namespaces. A. True B. False

Answer 41

B. False In Kubernetes, names of resources need to be unique within a namespace, but not across namespaces.

Question 42

In Kubernetes, namespace-based scoping is applicable for cluster-wide objects (e.g. StorageClass, Nodes, PersistentVolumes, etc.) A. True B. False

Answer 42

B. False In Kubernetes, namespace-based scoping is applicable only for namespaced objects (e.g. Deployments, Services, etc) and not for cluster-wide objects (e.g. StorageClass, Nodes, PersistentVolumes, etc). Namespaces.

Question 43

Which Kubernetes component manages containers on an individual node? A. kube-scheduler B. kubelet C. kube-controller-manager D. kube-proxy

Answer 43

B. kubelet The kubelet is the agent that manages containers on each node.