7. K8S

DAY-01: 

K8S:

vim minikunbe.sh

sudo apt update -y
sudo apt upgrade -y
sudo apt install curl wget apt-transport-https -y
sudo curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh
sudo curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64
sudo mv minikube-linux-amd64 /usr/local/bin/minikube
sudo chmod +x /usr/local/bin/minikube
sudo minikube version
sudo curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
sudo curl -LO "https://dl.k8s.io/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl.sha256"
sudo echo "$(cat kubectl.sha256) kubectl" | sha256sum --check
sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl
sudo minikube start --driver=docker --force

imperative method: we use commands to create pod
kubectl run pod1 --image nginx
kubectl: clt
run: create 
pod1: pod name
nginx: image

kubectl get pods
kubectl get pod
kubect1 get po
kubect1 get po -o wide
kubectl describe pod pod1 

Declarivte method: we use file (manifest) to create pod
manifest file is on yaml format.

vim pod.yml

apiVersion: v1
kind: Pod
metadata:
  name: pod3
spec:
  containers:
    - name: cont1
      image: rahamshaik/moviesrepopaytm:latest

kubectl create -f pod.yml
kubectl delete pod pod3


DRAWBACKS:
1. if a pod is delete we cant get back.

HISTORY:
1  ll
    2  mkdir k8s
    3  cd k8s/
    4  vim minikube.sh
    5  sh minikube.sh
    6  minikube status
    7  kubectl get node
    8  kubectl run pod1 --image nginx
    9  kubectl get pods
   10  kubectl get pod
   11  kubectl get po
   12  kubectl run pod2 --image rahamshaik/moviesrepopaytm:latest
   13  kubectl get po
   14  kubectl get po -o wide
   15  kubectl describe pod pod1
   16  vim pod.yml
   17  kubectl create -f pod.yml
   18  vim pod.yml
   19  vim pod.yml
   20  kubectl create -f pod.yml
   21  kubectl get po
   22  kubectl describe pod pod3
   23  kubectl get po
   24  kubectl delete pod pod3
   25  kubectl get po
   26  cat pod.yml
   27  history


========================================================

DAY-03: 24-07-2023: RS, DEPLOYMENT

RS: it will create multiple replicas of same pod
if we delete one pod it will create another
by using labels we can identify all the replicas of pods.
selector will select all the pods with same replicas.

apiVersion: apps/v1
kind: ReplicaSet
metadata:
  labels:
    app: swiggy
  name: swiggy-rs
spec:
  replicas: 3
  selector:
    matchLabels:
      app: swiggy
  template:
    metadata:
      labels:
        app: swiggy
    spec:
      containers:
      - name: cont1
        image: rahamshaik/moviesrepopaytm:v2

kubectl apply -f filename.yml

kubectl get rs
kubectl get rs -o wide
kubectl describe rs swiggy-rs

kubectl get po
kubectl get po -o wide
kubectl describe pod podname
kubectl get po --show-labels
kubectl delete po -l app=swiggy

DRAWBACK:
If we update the image replicaset will wont work here.

DEPLOYMENT:
It is more advance than RS.
we use this on real deployment.

deployment -- > replicaset -- > pods


apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: swiggy
  name: swiggy-deploy
spec:
  replicas: 3
  selector:
    matchLabels:
      app: swiggy
  template:
    metadata:
      labels:
        app: swiggy
    spec:
      containers:
      - name: cont1
        image: nginx

kubectl apply -f filename.yml

kubectl get deploy
kubectl get deploy -o wide
kubectl describe deploy swiggy-deploy
kubectl delete deploy swiggy-deploy

kubectl get po
kubectl get po -o wide
kubectl describe pod podname
kubectl get po --show-labels
kubectl delete po -l app=swiggy

HISTORY:

 1  vim .bashrc 
    2  source .bashrc 
    3  vim kops.sh
    4  sh kops.sh 
    5  ls -a
    6  vim .aws/config 
    7  vim .aws/credentials 
    8  sh kops.sh 
    9  vim .aws/credentials 
   10  sh kops.sh 
   11  cat kops.sh 
   12  export KOPS_STATE_STORE=s3://heera.k8s.local
   13  kops validate cluster --wait 10m
   14  kops get cluster
   15  kubectl get no
   16  vim abc.yml
   17  kubectl api-resources
   18  kubectl api-resources | grep -i replica
   19  vim abc.yml 
   20  cat abc.yml 
   21  kubectl create -f abc.yml 
   22  vim abc.yml 
   23  kubectl create -f abc.yml 
   24  vim abc.yml 
   25  kubectl create -f abc.yml 
   26  cat abc.yml 
   27  vim abc.yml 
   28  kubectl create -f abc.yml 
   29  vim abc.yml 
   30  kubectl create -f abc.yml 
   31  vim abc.yml 
   32  kubectl create -f abc.yml 
   33  cat abc.yml 
   34  kubectl delete rs swiggy-rs
   35  vim abc.yml 
   36  kubectl create -f abc.yml 
   37  vim abc.yml 
   38  kubectl create -f abc.yml 
   39  vim abc.yml 
   40  kubectl create -f abc.yml 
   41  vim abc.yml 
   42  kubectl create -f abc.yml 
   43  kubectl get po
   44  kubectl describe pod swiggy-rs-khghk
   45  kubectl get po --show labels 
   46  kubectl get po --show-labels 
   47  kubectl run pod1 --image nginx
   48  kubectl get po --show-labels 
   49  kubectl run pod2 --image nginx
   50  kubectl run pod3 --image nginx
   51  kubectl get po --show-labels 
   52  kubectl delete pod --labels app=swiggy
   53  kubectl delete pod app=swiggy
   54  kubectl delete --help
   55  kubectl delete pod -l app=swiggy
   56  kubectl get po
   57  kubectl delete pod pod1
   58  kubectl get po
   59  kubectl get rs 
   60  kubectl get rs -o wide
   61  kubectl describe rs swiggy-rs
   62  kubectl get po
   63  kubectl scale rs/swiggy-rs --replicas=10
   64  kubectl get po
   65  kubectl get po -o wide
   66  kubectl delete pod2 pod3
   67  kubectl delete pod pod2 pod3
   68  kubectl get po -o wide
   69  kubectl scale rs/swiggy-rs --replicas=20
   70  kubectl get po -o wide
   71  kubectl scale rs/swiggy-rs --replicas=5
   72  kubectl get po -o wide
   73  kubectl delete pod swiggy-rs-khghk
   74  kubectl delete pod swiggy-rs-2fnf8
   75  kubectl get po -o wide
   76  cat abc.yml 
   77  vim abc.yml 
   78  kubectl create -f abc.yml 
   79  kubectl get deploy
   80  kubectl get deploy -o wide
   81  kubectl describe deploy swiggy-deploy
   82  kubectl describe deploy swiggy-deploy | grep -i image
   83  kubectl edit deploy/swiggy-deploy
   84  kubectl describe deploy swiggy-deploy | grep -i image
   85  kubectl edit deploy/swiggy-deploy
   86  kubectl describe deploy swiggy-deploy | grep -i image
   87  kubectl get deploy
   88  kubectl get rs
   89  kubectl get pod
   90  kubectl scale deploy/swiggy-deploy --replicas=10
   91  kubectl get pod -o wide
   92  cat abc.yml 
   93  kubectl delete deploy swiggy-deploy
   94  kubectl get rs
   95  vim abc.yml 
   96  kubectl create -f abc.yml 
   97  kubectl get rs
   98  kubectl edit rs/swiggy-rs
   99  vim abc.yml 
  100  kubectl create -f abc.yml 
  101  kubectl delete rs swiggy-rs
  102  kubectl create -f abc.yml 
  103  kubectl get rs
  104  kubectl edit rs/swiggy-rs
  105  kubectl describe rs swiggy-rs | grep -i image
  106  kubectl get po
  107  kubectl describe pod swiggy-rs-6x9gc
  108  kubectl delete rs swiggy-rs
  109  kubectl describe pod swiggy-rs-6x9gc
  110  kubectl delete rs swiggy-rs
  111 
  112  kubectl delete -h
  113  kubectl delete --help
  114  kops get cluster
  115  kops delete cluster --name mtpk.k8s.local --yes
  116  history


=====================================================================================

DAY-04: 25-07-2023: NAMESPACE, DEAMONSET, KUBECOLOR

NAMESPACE: It is used to divide the cluster to multiple teams.
dev team= dev namespace 
test team= test namespace
it is used to isloate the resources.

default: if we create any resource it will go under default namespace
kube-node-lease: if we take an object from another node it will store on this ns.
kube-public: it will make the resource available for all users.
kube-system: k8s will create its own resources for itself on this ns.

kubectl get po -n default
kubectl get po -n kube-node-lease
kubectl get po -n kube-public
kubectl get po -n kube-system



kubectl config set-context --current --namespace=dev
kubectl config view --minify
kubectl config view --minify | grep -i namespace


DAEMOSET: It will create one pod on all each node of the cluster.
mainly we use if to create fluentd and elasticsearch pods to fetch logs.


KUBECOLOR: To apply colors for the k8s

wget https://github.com/hidetatz/kubecolor/releases/download/v0.0.25/kubecolor_0.0.25_Linux_x86_64.tar.gz
tar -zxvf kubecolor_0.0.25_Linux_x86_64.tar.gz
./kubecolor
chmod +x kubecolor
mv kubecolor /usr/local/bin/
kubecolor get po
kubecolor get po -n kube-system


HISTORY:

    1  vim .bashrc
    2  source .bashrc
    3  vim kops.sh
    4  sh kops.sh
    5  vim kops.sh
    6  sh kops.sh
    7  cat kops.sh
    8  export KOPS_STATE_STORE=s3://heera.k8s.local
    9  kops validate cluster --wait 10m
   10  kubectl get ns
   11  kubectl run pod1 --image nginx
   12  kubectl describe pod pod1
   13  kubectl get po
   14  kubectl get po -ns default
   15  kubectl get po -n default
   16  kubectl get po -n kube-node-lease
   17  kubectl get po -n kube-public
   18  kubectl get po -n kube-system
   19  kubectl get po
   20  kubectl get ns
   21  kubectl create ns dev
   22  kubectl get ns
   23  kubectl config set-context --current-namespace=dev
   24  kubectl config set-context --current --namespace=dev
   25  kubectl config minify
   26  kubectl config minify
   27  kubectl config view --minify
   28  kubectl config view --minify | grep -i ns
   29  kubectl config view --minify | grep -i namespace
   30  kubectl run dev1 --image nginx
   31  kubectl run dev2 --image nginx
   32  kubectl run dev3 --image nginx
   33  kubectl get po
   34  kubectl create ns test
   35  kubectl config set-context --current --namespace=test
   36  kubectl config view --minify | grep -i namespace
   37  kubectl get po
   38  kubectl get po -n dev
   39  kubectl get po -n dev --show-labels
   40  vim abc.yml
   41  kubectl create -f abc.yml
   42  kubectl get rs
   43  kubectl config set-context --current --namespace=dev
   44  kubectl get rs
   45  kubectl get rs -n test
   46  kubectl get po -n test
   47  kubectl get po -n test -l app=swiggy
   48  kubectl describe pod swiggy-rs-h6ghx -n test
   49  kubectl get ns
   50  kubectl delete ns test
   51  kubectl delete ns dev
   52  kubectl get ns
   53  kubectl config view --minify | grep -i namespace
   54  kubectl config set-context --current --namespace=default
   55  kubectl get ns
   56  kubectl config view --minify | grep -i namespace
   57  vim daemonset.yml
   58  kubectl create -f daemonset.yml
   59  kubectl get po
   60  kubectl get po --all
   61  kubectl get po -n --all
   62  kubectl ap-resources
   63  kubectl api-resources
   64  kubectl get ds
   65  kubectl get ds -n kube-system
   66  vim daemonset.yml
   67  kubectl get ds -n kube-system
   68  alias kubectl="kubecolor"
   69  command -v kubecolor >/dev/null 2>&1 && alias kubectl="kubecolor"
   70  kubectl get po -n kube-system
   71  kubecolor get po -n kube-system
   72  vim .bashrc
   73  source .bashrc
   74  kubecolor get po -n kube-system
   75   wget https://github.com/hidetatz/kubecolor/releases/download/v0.0.25/kubecolor_0.0.25_Linux_x86_64.t                                                                                                                                                                                                       ar.gz
   76  ll
   77  tar -zxvf kubecolor_0.0.25_Linux_x86_64.tar.gz
   78  ll
   79  ./kubecolor
   80  kubecolor
   81  chmod +x kubecolor
   82  mv kubecolor /usr/local/bin/
   83  ls /usr/local/bin/kubecolor
   84  kubecolor get po
   85  kubecolor get po -n kube-system
   86  histroy

==================================================
DAY-05: 26-07-2023: SVC (CIP, NP, LB)

SERVICE: it is used to expose an application.

TYPES:
1. CLUSTERIP: It will work inside the cluster.
it will not expose to outer world.

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: swiggy
  name: swiggy-deploy
spec:
  replicas: 3
  selector:
    matchLabels:
      app: swiggy
  template:
    metadata:
      labels:
        app: swiggy
    spec:
      containers:
      - name: cont1
        image: rahamshaik/trainservice:latest
        ports:
          - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: sv1
spec:
  type: ClusterIP
  selector:
    app: swiggy
  ports:
    - port: 80

DRAWBACK:
We cannot use app outside.

2. NODEPORT: It will expose our application in a particular port.
Range: 30000 - 32767 (in sg we need to give all traffic)

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: swiggy
  name: swiggy-deploy
spec:
  replicas: 3
  selector:
    matchLabels:
      app: swiggy
  template:
    metadata:
      labels:
        app: swiggy
    spec:
      containers:
      - name: cont1
        image: rahamshaik/trainservice:latest
        ports:
          - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: abc
spec:
  type: NodePort
  selector:
    app: swiggy
  ports:
    - port: 80
      targetPort: 80
      nodePort: 31111

DRAWBACK:
PORT RESTRICTION.

3. LOADBALACER: It will expose our app and distribute load blw pods.

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: swiggy
  name: swiggy-deploy
spec:
  replicas: 3
  selector:
    matchLabels:
      app: swiggy
  template:
    metadata:
      labels:
        app: swiggy
    spec:
      containers:
      - name: cont1
        image: rahamshaik/trainservice:latest
        ports:
          - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: abc
spec:
  type: LoadBalancer
  selector:
    app: swiggy
  ports:
    - port: 80
      targetPort: 80


HISTORY:

 1  cat kops.sh
    2  aws s3 ls
    3  sh kops.sh
    4  cat kops.sh
    5  export KOPS_STATE_STORE=s3://heera.k8s.local
    6   kops validate cluster --wait 10m
    7  kubecolor get po
    8  vim abc.yml
    9  vim abc.yml
   10  kubectl api-resources
   11  kubectl api-resources | grep -i service
   12  vim abc.yml
   13  kubectl create -f abc.yml
   14  kubecolor get svc
   15  kubecolor get svc -o wide
   16  kubecolor describe svc sv1
   17  ll
   18  kubecolor delete -f abc.yml
   19  kubecolor get svc
   20  kubecolor get deploy
   21  vim abc.yml
   22  kubecolor create -f abc.yml
   23  kubecolor get svc
   24  kubecolor get deploy
   25  kubecolor get svc,deploy
   26  kubecolor get svc,deploy,rs
   27  kubecolor get deploy
   28  kubecolor get rs
   29  kubecolor get po
   30  kubecolor get po -o wide
   31  vim abc.yml
   32  kubecolor apply -f abc.yml
   33  vim abc.yml
   34  vim .bashrc
   35  source .bashrc
   36  k get po
   37  vim .bashrc
   38  source .bashrc
   39  k get po
   40  vim .bashrc
   41  kubecolor delete -f abc.yml
   42  vim abc.yml
   43  kubecolor create -f abc.yml
   44  vim abc.yml
   45  history