Learning to use Kubernetes
"Kubernetes is an open source project that enables software teams of all sizes, from a small startup to a Fortune 100 company, to automate deploying, scaling, and managing applications on a group or cluster of server machines. These applications can include everything from internal-facing web applications like a content management sysrtem to marquee web properties like Gmail to big data processing."
The project goal is to create a kubernetes cluster with: nginx, phpmyadmin, wordpress, ftps, mysql, grafana, telegraf and influxdb.
To get familiar with useful software and learn how to configure and run all of it in k8s.
git clone https://github.com/kukinpower/ft_services.git
cd ft_services
sh setup.sh
Feel free to use my_dashboard.sh to see pretty k8s custom dashboard in your cli
sh my_dashboard.sh
My k8s aliases
alias k=kubectl
alias ks="k get svc"
alias kp="k get po"
alias kd="k get deployments"
alias md="minikube stop && minikube delete"
Add this to ~/.zshrc
source <(kubectl completion zsh)
kubectl get pods
kubectl get replicaset
kubectl create deployment nginx-deployment --image=nginx
kubectl edit deployment [name]
kubectl logs [pod name]
kubectl exec -it [pod name] -- bin/sh
kubectl cp [pod name]:[dir or file name] [desired path to dir or file name]
Kubernetes has a plug-n-play architecture that allows to extend it when need to.
Health checks are available from a box. Such as: TCP, HTTP or container execution.
Pod is container in k8s
Pods can be assigned to nodes
Pods can use persistent volumes to store data
In Kubernetes, all containers run in pods.
Some examples:
kubectl create deployment nginx --image=nginx:1.10.0
kubectl get pods to view the pods.
To expose the nginx container outside Kubernetes
kubectl expose deployment nginx --port 80 --type LoadBalancer
kubectl get services to view services
kubectl scale deployment nginx --replicas 3
creates 3 replica pods
built-in pod documentation kubectl explain command
kubectl describe pods [NAME] to get more info
kubectl port-forward to map a local port to a port inside the monolith pod
kubectl port-forward monolith 10080:80
How to see which node a pod belongs?
kubectl get pod -o=custom-columns=NODE:.spec.nodeName,NAME:.metadata.name --all-namespaces
or simply kubectl get pods -o wide
kubectl logs -f monolith to get a stream of logs in real time
Deployment manages a ReplicaSet Replicaset manages a Pod Pod is an abstraction of Container