Certified Kubernetes Administrator V 1.19
- Manage role based access control (RBAC)
- Use Kubeadm to install a basic cluster
- Manage a highly-available Kubernetes cluster
- Provision underlying infrastructure to deploy a Kubernetes cluster
- Perform a version upgrade on a Kubernetes cluster using Kubeadm
- Implement etcd backup and restore
- Understand deployments and how to perform rolling update and rollbacks
- Use ConfigMaps and Secrets to configure applications
- Know how to scale applications
- Understand the primitives used to create robust, self-healing, application deployments
- Understand how resource limits can affect Pod scheduling
- Awareness of manifest management and common templating tools
- Understand host networking configuration on the cluster nodes
- Understand connectivity between Pods
- Understand ClusterIP, NodePort, LoadBalancer service types and endpoints
- Know how to use Ingress controllers and Ingress resources
- Know how to configure and use CoreDNS
- Choose an appropriate container network interface plugin
- Understand storage classes, persistent volumes
- Understand volume mode, access modes and reclaim policies for volumes
- Understand persistent volume claims primitive
- Know how to configure applications with persistent storage
- Evaluate cluster and node logging
- Understand how to monitor applications
- Manage container stdout & stderr logs
- Troubleshoot application failure
- Troubleshoot cluster component failure
- Troubleshoot networking
practice pratice pratice
Get familiar with:
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Familiarize yourself with the documentation, initially concepts and mostly tasks, kubectl explain command, kubectl cheatsheet, and kubectl commands reference
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https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands
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kubectl api-versionsandkubectl api-resourceswihgrepfor a specific resoruce e.g. pv, pvc, deployment, storageclass, ..etc can help figure out the apiVersion, and kind combined with explain below will help in constructing the yaml manifest -
kubectl explain --recurisve to construct out any yaml manifest you need and find its specd and details
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When using kubectl for investigations and troubleshooting utilize the wide output it gives your more details
$kubectl get pods -o wide --show-labels --all-namespaces
or
$kubectl get pods -o wide --show-labels -A # -A is quicker than --all-namespaces
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In
kubectlutilizie--all-namespaces or better -Ato ensure deployments, pods, objects are on the right name space, and right desired state -
for events and troubleshooting utilize kubectl describe if its pod/resource related and logs if it is application issue related
$kubectl describe pods <PODID> # for pod, deployment, other k8s resource issues/events
$kubectl logs <PODID> # for container/application issues like crash loops
- fast with kubectl e.g. the '-o yaml' in conjuction with
--dry-run=clientallows you to create a manifest template from an imperative spec, combined with--editit allows you to modify the object before creation
kubectl create service clusterip my-svc -o yaml --dry-run=client > /tmp/srv.yaml
kubectl create --edit -f /tmp/srv.yaml
- use kubectl aliases to speed up and reduce typo errors, practice these alaises early at your work and study for the exam. some example aliases:
alias k='kubectl'
alias kg='kubectl get'
alias kgpo='kubectl get pod'
alias kcpyd='kubectl create pod -o yaml --dry-run=client'
alias ksysgpo='kubectl --namespace=kube-system get pod'
alias kd='kubectl delete'
alias kdf='kubectl delete -f'
## for quick deletes you can add --force --grace-period=0 **Not sure if it is a good idea if you are in a production cluster**
alias krmgf='kubectl delete --grace-period 0 --force'
alias kgsvcoyaml='kubectl get service -o=yaml'
alias kgsvcwn='watch kubectl get service --namespace'
alias kgsvcslwn='watch kubectl get service --show-labels --namespace'
#example usage of aliases
krmgf nginx-8jk71 # kill pod nginx-8jk71 using grace period 0 and force
Double check if the course is uptodate with the latest exam information (e.g. api, or curicuilim)
- Mumshad CKA with practice tests and mock exams - Highly recommended
- Killer.sh CKA simulator ⟹ use code walidshaari for 20% discount - they update frequently
- LinuxAcademy/ACloudGuru CKA course # labs last checked were updated to 1.18
- rx-m online CKA course
- Pluralsight CKA course
- Duffie Cooly hands-on CKA video using KinD and accompanying notes
- Stilian Stoilov practice questions - 40+ tasks with increasing difficulty.
Install
apt install asciinema
Start
asciinema rec
Stop
CTRL + D