k8s beginner 01 - pod concept
PODs
* container are isolated in k8s objects which is known as a pod or minion
* a pod is single instance of a an application
* a pod the smallest object that can be created in k8s cluster
simplest
* a single node cluster
* using a single pod
* which contains a single container
scaling
* scaling is NOT adding more containers to a pod
* scaling creates new pods
* is the node limit reached create a new node in a cluster within scalling new pods
multi container
* containers in a pod can share a network and storage as well
* helper container dies also like a regulary container if the pod dies
* in k8s helper container can combine both in a pod which can share storage to each other
deploy pods
* kubectl pulls from docker hub by default
demo
# pull and run nginx container
> kubectl run nginx --image nginx
# show running pods
> kubectl get pods
# describe pod
> kubectl describe pods nginx
# get pod details like host
> kubectl get pods -o wide
# delete pod
> kubectl delete pod nginx
“kubectl
describe
” is a very powerfull command!
see: kubernetes.io/docs/concepts
and: kubernetes.io/docs/concepts/workloads/pods/pod-overview/
16-09-2021