KUBERNETES LEARNING PHASE 1 - BASIC COMMANDS
·2 mins
This post will only includes scenario based Kubernetes problem and the commands/debugging steps. It will be updated whenever I learn something new.
For Installation of Kubernetes refer here: https://kubernetes.io/docs/tasks/tools/
Case 1: Get all pods in a namespace #
kubectl get pods -n <namespace_name>
Case 2: Get all namespaces #
kubectl get namespaces
OR
kubectl get ns
Case 3: Create pods with a name and image in a particular namespace #
kubectl run <pod_name> --image=<image_name> -n <namespace>
e.g.
kubectl run redis --image=redis -n my-namespace
Case 4: Get all pods in all the namespaces #
kubectl get pods --all-namespaces
Case 5: Get all replicasets #
kubectl get replicaset
Case 6: Create pods using yaml file #
kubectl apply -f abc.yml -n namespace
- abc.yaml or abc.yml* file:
apiVersion: v1
kind: Pod
metadata:
name: new-pod
label:
type: linux
spec:
containers:
-name: redis
image: redis
Case 7: Create deployment using yaml file #
kubectl apply -f deployment.yml
deployment.yml file is having
apiVersion: apps/v1
kind: Deployment
metadata:
name: new-deployment
spec:
replicas: 3
selector:
matchLabels:
name: abc-pod
template:
metadata:
labels:
name: abc-pod
spec:
containers:
- name: abc-container
image: nginx
command:
- sh
- "-c"
- echo Hello Kubernetes! && sleep 3600
Here important points are:
- apiVersion should follow the way apps/v1 or apps/v
- kind is case sensitive
- matchlabels.name should be same as metadata.labels.name
- You can specify the replica number and that many pods will be created.
- When this deployment will be created, a replica set, 3 pods, one deployment will be created.
Case 8: Get all details of the pod #
kubectl describe pod <pod_name> -n <namespace>
Case 9: Get all pods, replicaset, deployment and services present #
kubectl get all
Case 10: Editing an existing replicaset #
kubectl edit replicaset <replicaset_name>
There will be an another post soon dealing with more kubernetes day to day used commands.