Kubernetes

Links

• https://kubernetes.io/
• kubectl Cheat Sheet
• https://training.play-with-kubernetes.com/
• https://labs.play-with-k8s.com/
• Kubernetes Failure Stories
• https://crossplane.io/
• Matchbox Kubernetes network boot
• Debugging network stalls on Kubernetes
• https://kubernetes.io/docs/home/

Certification

• https://www.cncf.io/certification/expert/cka/
• https://kubernetes.io/docs/tasks/
• https://github.com/arush-sal/cka-practice-environment
• https://github.com/kelseyhightower/kubernetes-the-hard-way
• https://jvns.ca/blog/2017/08/05/how-kubernetes-certificates-work/

Create a Cluster

• Official Kubernetes "Getting started"
• On Azure

Cloud Provider

VMWARE

• vSphere Cloud Provider
• Configuring vSphere Volumes for Kubernetes
• PersistentVolume Storage Options on vSphere
• vSAN as Persistent Storage for a Kubernetes Cluster
• Deploying a Kubernetes Cluster on vSphere with CSI and CPI
• Dynamic Provisioning and StorageClass API
• LAB GUIDE - KUBERNETES AND STORAGE WITH THE VSPHERE CLOUD PROVIDER - STEP BY STEP

Basic Commands

List

PODs on ALL Namespaces

kubectl get pods --all-namespaces

All Namespaces

kubectl get namespaces

Remote execution/console login

kubectl exec -it podname -n namespace -- bash

Scale

kubectl scale --replicas=3 deployment/foo    

Host Affinity

• Assigning Pods to Nodes

spec:
  affinity:
    nodeAffinity:
      requiredDuringSchedulingIgnoredDuringExecution:
        nodeSelectorTerms:
        - matchExpressions:
          - key: kubernetes.io/hostname
            operator: In
            values:
            - cluster-nodepoolname-vmisntance00.domain
            - cluster-nodepoolname-vmisntance01.domain
            - cluster-nodepoolname-vmisntance02.domain
            - cluster-nodepoolname-vmisntance03.domain

By agentpool

spec:
  affinity:
    nodeAffinity:
      requiredDuringSchedulingIgnoredDuringExecution:
        nodeSelectorTerms:
        - matchExpressions:
          - key: agentpool
            operator: In
            values:
            - ssd

PODs

• https://coreos.com/rkt/
• https://www.docker.com/
  • https://hub.docker.com/

Port Forward

kubectl port-forward pod/kuard2 8000:8080

Node afinity

spec
  .
  .
  .
  strategy:
  .
  .
  .
  template:
    metadata:
      .
      .
      .
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: agentpool
                operator: In
                values:
                - svc01
                - svc02

CronJob

kubectl create job --from=cronjob/<name of cronjob> <name of job>
kubectl create job --from=cronjob/pgdump pgdump-manual-001

Network

Ingress

• https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/annotations.md
• https://docs.microsoft.com/pt-br/azure/aks/ingress-static-ip

Access pod by hostname

FQDN:
auto-generated-name.my-svc.my-namespace.svc.cluster.local

Persistent Storage

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: task-pv-claim
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 3Gi

kind: PersistentVolume
apiVersion: v1
metadata:
  name: task-pv-storage
  labels:
    type: local
spec:
  storageClassName: managed-standard
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data"

kubectl get pv task-pv-storage

kind: Pod
apiVersion: v1
metadata:
  name: task-pv-pod
spec:
  volumes:
    - name: task-pv-storage
      persistentVolumeClaim:
       claimName: task-pv-storage
  containers:
    - name: task-pv-container
      image: nginx
      ports:
        - containerPort: 80
          name: "http-server"
      volumeMounts:
        - mountPath: "/usr/share/nginx/html"
          name: task-pv-storage

Tools

• http://fabric8.io/guide/getStarted/helm.html
• NGINX
• K9S Github k9s
• STERN
• KUARD

API

• Spring Cloud Kubernetes