k8s/StudyNotes
k8s/StudyNotes/k8sDesignCluster
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:
Setup env
alias k=kubectl export do="-o yaml --dry-run=client"- 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
- kubectl clusterInfo
- kubeadm
- deploys all the kubernetes services downloaded from web
- Kube-Scheduler
- Filter Nodes (Pod cant fit)
- 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:
- hard:
- spec: