Getting a local cluster up and running

Once Minikube and Kubectl are installed, get a cluster up and running. It is worthwhile to know the versions of the tools you're using, as Kubernetes is a fairly fast-moving project, and if you need to get assistance from the community, knowing which versions of these common tools will be important.

The versions of Minikube and kubectl I used while writing this are:

• Minikube: version 0.22.3

• kubectl: version 1.8.0

You can check the version of your copy with the following commands:

minikube version

This will output a version:

minikube version: v0.22.3

If you haven't already done so while following the installation instructions, start a Kubernetes with Minikube. The simplest way is using the following command:

minikube start

This will download a virtual machine image and start it, and Kubernetes on it, as a single-machine cluster. The output will look something like the following:

Downloading Minikube ISO
 106.36 MB / 106.36 MB [============================================] 100.00% 0s
Getting VM IP address...
Moving files into cluster...
Setting up certs...
Connecting to cluster...
Setting up kubeconfig...
Starting cluster components...
Kubectl is now configured to use the cluster.

Minikube will automatically create the files needed for kubectl to access the cluster and control it. Once this is complete, you can get information about the cluster to verify it is up and running.

First, you can ask minikube about its status directly:

minikube status
minikube: Running
cluster: Running
kubectl: Correctly Configured: pointing to minikube-vm at 192.168.64.2

And if we ask kubectl about its version, it will report both the version of the client and the version of the cluster that it is communicating with:

kubectl version

The first output is the version of the kubectl client:

Client Version: version.Info{Major:"1", Minor:"7", GitVersion:"v1.7.5", GitCommit:"17d7182a7ccbb167074be7a87f0a68bd00d58d97", GitTreeState:"clean", BuildDate:"2017-08-31T19:32:26Z", GoVersion:"go1.9", Compiler:"gc", Platform:"darwin/amd64"}

Immediately after, it will communicate and report the version of Kubernetes on your cluster:

Server Version: version.Info{Major:"1", Minor:"7", GitVersion:"v1.7.5", GitCommit:"17d7182a7ccbb167074be7a87f0a68bd00d58d97", GitTreeState:"clean", BuildDate:"2017-09-11T21:52:19Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"linux/amd64"}

And we can use kubectl to ask for information about the cluster as well:

kubectl cluster-info

And see something akin to the following:

Kubernetes master is running at https://192.168.64.2:8443

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

This command primarily lets you know the API server that you're communicating with is up and running. We can ask for the specific status of the key internal components using an additional command:

kubectl get componentstatuses

NAME                 STATUS    MESSAGE              ERROR
scheduler            Healthy   ok
etcd-0               Healthy   {"health": "true"}
controller-manager   Healthy   ok

Kubernetes also reports and stores a number of events that you can request to see. These show what is happening within the cluster:

kubectl get events

LASTSEEN   FIRSTSEEN   COUNT     NAME       KIND      SUBOBJECT   TYPE      REASON                    SOURCE                 MESSAGE
2m         2m          1         minikube   Node                  Normal    Starting                  kubelet, minikube      Starting kubelet.
2m         2m          2         minikube   Node                  Normal    NodeHasSufficientDisk     kubelet, minikube      Node minikube status is now: NodeHasSufficientDisk
2m         2m          2         minikube   Node                  Normal    NodeHasSufficientMemory   kubelet, minikube      Node minikube status is now: NodeHasSufficientMemory
2m         2m          2         minikube   Node                  Normal    NodeHasNoDiskPressure     kubelet, minikube      Node minikube status is now: NodeHasNoDiskPressure
2m         2m          1         minikube   Node                  Normal    NodeAllocatableEnforced   kubelet, minikube      Updated Node Allocatable limit across pods
2m         2m          1         minikube   Node                  Normal    Starting                  kube-proxy, minikube   Starting kube-proxy.
2m         2m          1         minikube   Node                  Normal    RegisteredNode            controllermanager      Node minikube event: Registered Node minikube in NodeController