03 - KUBERNETES

Question 1

What is kubernetes ?

Answer 1

kubernetes is s tool for running a bunch of different containers

Question 2

how des kubernetes manage the containers

Answer 2

it gets s configuration to describe how we want our containers to run and interect with each other

Question 3

enable kubernetes from UI for mac

Question 4

how to install k8s in linux

Answer 4

minikube

Question 5

what is a k8s cluster

Answer 5

a collection of nodes + a master to manage them

Question 6

Node on k8s

Answer 6

a virtual machine that will run our containers

Question 7

Pod in k8s

Answer 7

more or less a running container

Question 8

Deployment

Answer 8

monitors a set of pods, make sure they are running and restarts them if they crash

Question 9

service

Answer 9

provides an easy-to-remember URL to access a running container

Question 10

function of the k8s config file

Answer 10

tells k8s about the different deployments, pods, and services, referred to as objects

Question 11

sample k8s config file to create a Pod

Answer 11

build docker image
filename: posts.yaml

apiVersion: v1
kind: Pod
metadata:
name: posts
spec:
containers:
- name: posts
image: tagName/posts:0.0.1

Question 12

command to execute k8s config

Answer 12

kubectl apply -f posts.yaml

Question 13

display all pods

Answer 13

kubectl get pods

Question 14

how k8s handle latest tag on image name

Question 15

run command in pod

Answer 15

kubectl exec -it [pod-name] [cmd]

Question 16

show k8s logs

Answer 16

kubectl logs [pod_name]

Question 17

delete pod

Answer 17

kubectl delete pod [pod_name]

Question 18

describe pod

Answer 18

kubectl describe pod [pod_name]

Question 19

config file, creating a deployment

Answer 19

apiVersion: v1
kind: Deployment
metadata:
name: posts-depl
spec:
replicas: 1
selector:
matchlabels:
app: posts
template:
metadata:
labels :
app: posts
spec:
containers:
- name: posts
image: [tagename/posts:0.0.1]

Question 20

list all deployments

Answer 20

kubectl get deployments

Question 21

print out details about a specific deployment

Answer 21

kubect; describe deployment [depl name]

Question 22

create a deployment out of a config file

Answer 22

kubectl apply -f [config file name]

Question 23

delete a deployment

Answer 23

kubectl delete deployment [depl-name]

Question 24

updating the image used by a deployment

Answer 24

kubectl rollout restart deployment posts-depl

Question 25

types of k8s services

Answer 25

cluster IP
node port
load balancer
external name

Question 26

cluster IP

Answer 26

sets up an easy-to-remember URL to access a pod, only exposes pod to cluster

Question 27

node port

Answer 27

makes a pod accessible from outside the cluster, usually only for dev’t

Question 28

load balancer

Answer 28

makes a pod accessible from outside the cluster

Question 29

external name

Answer 29

redirects an in-cluster request to a CNAME url

Question 30

sample k8s config to create a service

Answer 30

apiVersion: v1
kind: Service
metadata:
name: posts-srv
spec:
type: NodePort
selector:
app: posts
ports:
- name: posts
protocol: TCP
port: 4000
targetPort: 4000

Question 31

steps to create a deployment for the event-bus

Answer 31

• build an image for the event bus
• push image to docker hub
• create a deployment for event-bus
• create a cluster IP service for event bus and posts

Question 32

ingress-nginx config file

Answer 32

apiVersion: networking.k8s.io/vqbeta1
kind: Ingress
metadata:
name: ingress-srv
annotations:
kubernetes.io/ingress.class: nginx
spec:
rules:
- host: posts.com
http:
paths:
- path: /posts
backend:
serviceName: posts-clusterip-srv
servicePost: 4000

Question 32

ingress-nginx install guide

Question 33

what is the use of skaffold

Answer 33

automates many tasks in a k8s dev environment
makes it easy to update code in a running pod
makes it easy to create/delete all objects tied to a project at once