k8s/StudyNotes

• k8s/StudyNotes/cubectl

• k8s/StudyNotes/Deployments

• k8s/StudyNotes/Pods

• k8s/StudyNotes/Services

• k8s/StudyNotes/SchedulingSelectors

• k8s/StudyNotes/TaintsAndTolerations

• k8s/StudyNotes/NodeSelectors+NodeAffinity

• k8s/StudyNotes/ResourceRequests

• k8s/StudyNotes/DaemonSets

• k8s/StudyNotes/kube-scheduler

• k8s/StudyNotes/Monitor&Logging

• k8s/StudyNotes/Rollout&Versioning

• k8s/StudyNotes/ClusterMaintenance&Upgrades

• k8s/StudyNotes/k8s-certs-security

• k8s/StudyNotes/RBAC

• k8s/StudyNotes/ServiceAccounts

• k8s/StudyNotes/ImageSecurity

• k8s/StudyNotes/SecurityDockerContainer

• k8s/StudyNotes/NetworkPolicies

• k8s/StudyNotes/Storage

• k8s/StudyNotes/LinuxNetworkNamespaces

• k8s/StudyNotes/k8sNetworking

  • https://kodekloud.com/

  • https://github.com/kodekloudhub/certified-kubernetes-administrator-course

  • Certified Kubernetes Administrator: https://www.cncf.io/certification/cka/

  • Exam Curriculum (Topics): https://github.com/cncf/curriculum

  • Candidate Handbook: https://www.cncf.io/certification/candidate-handbook

  • Exam Tips: http://training.linuxfoundation.org/go//Important-Tips-CKA-CKAD

  • Use the code – DEVOPS15 – while registering for the CKA or CKAD exams at Linux Foundation to get a 15% discount.

• Tips:

  • Very little can be edited in running pod field/property, rather edit deployment, as this will replace pod.

  • Find yaml config options for obj e.g. Pod  kubectl explain pod --recursive | grep -i scheduler 

  •  kubectl api-resources --namespaced=true 

  •  kubectl auth can-i --as peter get pods 

  • pod python app to access k8s api in container k8s/StudyNotes/k8sPythonApp

• kubeadm
  • deploys all the kubernetes services downloaded from web
• Kube-Scheduler
  1. Filter Nodes (Pod cant fit)
  2. Rank Nodes (Compare resources left, try to balance cpu/mem usage)
• kubelet - captain on each Worker Node
  • Registers with Master node, reports status and executes

  • Always manual install wget https://storage.googleapis.com/kubernetes-release/release/v1.xx.x/bin/linux/amd64/kubelet

    • Not kubeadm managed.
    • Needs tls bootstrap
• Kube-proxy - run on each node, service's virtual component
  • All pods can see all other pods, through POD Network, by IP/Name. Exposed through service: eg. db(IP)
  • Watches for service creation, and then configure network e.g. Iptables to forward to actual pod.
  • Install: download wget to install or
    • kubeadm will deploy it as deamon set to each pod in namespace kube-system

• kind: Deployments - Encapsulates ReplicaSet that Encapsulate Pods

  • Can have deployment and replacement policy

• kind: ResourceQuote

  • spec:
    • hard:
      • cpu: