A warm Hello to all the readers!
Today I am going to write about another component of Kubernetes. I was learning what is the role of Kubectl in K8s.
Kubectl is another command line interface tool just like Minikube. It is a CLI tool that interacts with Kubernetes cluster via Kubernetes API. It is used to manage K8s clusters.
Some of the operations that Kubectl perform include listing pods, nodes, deployments, master node, creating deployments, etc.
Kubectl is written in Golang and following command can be used to see the same
$ strings -20 $(which kubectl) | grep Go- To view list of nodes
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
minikube Ready master 5d v1.18.3- To create a new deployment
$ kubectl create deployment webapp --image=nodejscn/node
deployment.apps/webapp created- To view list of deployments
$ kubectl get deployments
NAME READY UP-TO-DATE AVAILABLE AGE
webapp 0/1 1 0 10s- To view list of pods
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
webapp-d9885cdd5-tlktg 0/1 ContainerCreating 0 18s- To see detailed information about pods, nodes, deployments
$ kubectl describe pods
Name: webapp-d9885cdd5-tlktg
Namespace: default
Priority: 0
Node: minikube/172.17.0.2
Start Time: Sun, 15 Nov 2020 20:35:46 +0530
Labels: app=webapp
pod-template-hash=d9885cdd5
Annotations: <none>
Status: Pending
IP: 172.18.0.6
IPs:
IP: 172.18.0.6
Controlled By: ReplicaSet/webapp-d9885cdd5
Containers:
node:
Container ID:
Image: nodejscn/node
Image ID:
Port: <none>
Host Port: <none>
State: Waiting
Reason: CreateContainerError
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-qxk9t (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
default-token-qxk9t:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-qxk9t
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Warning Failed 98m (x114 over 2d1h) kubelet, minikube Error: ImagePullBackOff
Normal Pulling 6m28s (x5074 over 2d22h) kubelet, minikube Pulling image "nodejscn/node"
Normal Pulled 87s (x5064 over 2d22h) kubelet, minikube Successfully pulled image "nodejscn/node"