concept kind in category kubernetes

This is an excerpt from Manning's book Kubernetes in Action, Second Edition MEAP V05. Login to get full access to this book.

3.1.3   Running a local cluster using kind (Kubernetes in Docker)

An alternative to Minikube, although not as mature, is kind (Kubernetes-in-Docker). Instead of running Kubernetes in a virtual machine or directly on the host, kind runs each Kubernetes cluster node inside a container. Unlike Minikube, this allows it to create multi-node clusters by starting several containers. The actual application containers that you deploy to Kubernetes then run within these node containers. The system is shown in the next figure.

Figure 3.4 Running a multi-node Kubernetes cluster using kind

In the previous chapter I mentioned that a process that runs in a container actually runs in the host OS. This means that when you run Kubernetes using kind, all Kubernetes components run in your host OS. The applications you deploy to the Kubernetes cluster also run in your host OS.

At the time of this writing, kind doesn’t provide a command to check the status of the cluster, but you can list cluster nodes using kind get nodes, as shown in the next listing.

Listing 3.4 Listing nodes using kind get nodes
$ kind get nodes
kind-worker2
kind-worker
kind-control-plane

This is an excerpt from Manning's book Core Kubernetes MEAP V02. Login to get full access to this book.

Once you have the basics in place, you can layer Kubernetes on top. You will need to perform an installation, and kubeadm, kind, and minikube tools do all of this for you.

6.2  Setting up kind

Kind is Kubernetes in a container. The majority of the labs will use kind to demonstrate the internals of Kubernetes, as well as to provide a playground to modify and test various Kubernetes items. This lab will get kind set up on your machine. Successive labs will expect this setup to be completed and will build upon it.

# Use the github API to get the latest version of kind
$ KIND_LATEST="https://api.github.com/repos/kubernetes-sigs/kind/releases/latest"
$ KIND_TAG=$(curl -s ${KIND_LATEST} | jq -r .tag_name)

# Use go to get the source code
$ GO111MODULE="on" go get sigs.k8s.io/kind@${KIND_TAG}
# Create a Kubernetes cluster with kind
$ kind create cluster