In this scenario, we want to configure the connection of the CLI kubectl with our Kubernetes cluster and explore first cluster details.
To interact with Kubernetes during this bootcamp we’ll use the command line interface, kubectl.
To check if kubectl is installed you can run the kubectl version command:
kubectl versionOK, kubectl is configured and we can see both, the version of the client as well as the server.
The client version is the kubectl version; the server version is the Kubernetes version installed on the master.
You can also see details about the build.
Type kubectl in the terminal to see its usage.
The common format of a kubectl command is: kubectl action resource.
This performs the specified action (like get, describe, create) on the specified resource (like node, container).
You can use --help after the command to get additional info about possible parameters (kubectl config --help).
Before we can access our cluster, we have to make sure that kubectl is correctly configured for the cluster.
To allow access to multiple clusters, kubectl allows to configure connections via contexts.
For every cluster connection there exists a context inside a kubeconfig configuration file.
By default, kubectl looks for a file named config in the $HOME/.kube directory.
To view all available contexts run:
kubectl config get-contextsThe currently selected context can be printed via:
kubectl config current-contextMake sure your current context targets arn:aws:eks:us-east-1:935581097791:cluster/training-cluster.
If not, switch to the correct context via: kubectl config use-context replace_with_context_name
To view the entire kubeconfig, enter this command:
kubectl config viewLet’s view the cluster details.
We’ll do that by running kubectl cluster-info:
kubectl cluster-infoThe command prints the address of the K8s control plane and cluster services.
To view the nodes in the cluster, run the kubectl get nodes command:
kubectl get nodesThis command shows all nodes that can be used to host our applications. We can see all available nodes and that their status is ready (they are ready to accept applications for deployment).
We can use the output option -o wide, to display more detailed information for most K8s resources:
kubectl get nodes -o wideHere, we can additionally see the OS image of the nodes and node IPs.
For a fully detailed view of a resource, including usage and events, we can use the describe command instead:
kubectl describe nodes replace_with_node_nameAdapted from https://kubernetes.io/docs/tutorials/ licenced under Creative Commons Attribution 4.0 International.