KIND - Kubernetes IN Docker

We can easily up and running K8S cluster for testing, This very lightweight as compared to other local setups.

This post is a reference for those who are trying to install the Kubernetes cluster on your ubuntu machine.

My Ubuntu 18.04 TLS server is a VirtualBox VM and I have installed the following dependencies on that server.

1. Install Docker

sudo apt-get update
sudo apt-get install apt-transport-https ca-certificates curl gnupg-agent software-properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
sudo apt-key fingerprint 0EBFCD88
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io

2. Install GO Language
https://golang.org/dl/

$ wget https://dl.google.com/go/go1.13.4.linux-amd64.tar.gz
$sudo tar -C /usr/local -xzf go1.13.4.linux-amd64.tar.gz
$ export PATH=$PATH:/usr/local/go/bin
$ go version
go version go1.13.4 linux/amd64

3. kubectl

 $ curl -LO https://storage.googleapis.com/kubernetes-release/release/`curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt`/bin/linux/amd64/kubectl
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 44.5M  100 44.5M    0     0  1209k      0  0:00:37  0:00:37 --:--:-- 1182k
$ chmod +x ./kubectl
$ sudo mv ./kubectl /usr/local/bin/kubectl

Now install KIND

https://github.com/kubernetes-sigs/kind

$ GO111MODULE="on" go get sigs.k8s.io/kind@v0.5.1
go: finding sigs.k8s.io v0.5.1
$ rm go1.13.4.linux-amd64.tar.gz
$ export PATH=$PATH:/home/ajeesh/go/bin
$ kind version
v0.5.1
$ kind create cluster
Creating cluster "kind" ...
 ✓ Ensuring node image (kindest/node:v1.15.3) 🖼
 ✓ Preparing nodes 📦
 ✓ Creating kubeadm config 📜
 ✓ Starting control-plane 🕹️
 ✓ Installing CNI 🔌
 ✓ Installing StorageClass 💾
Cluster creation complete. You can now use the cluster with:
export KUBECONFIG="$(kind get kubeconfig-path --name="kind")"
kubectl cluster-info

   $ export KUBECONFIG="$(kind get kubeconfig-path --name="kind")"
  $ kind get kubeconfig-path
/home/ajeesh/.kube/kind-config-kind

$ docker ps
CONTAINER ID        IMAGE                  COMMAND                  CREATED             STATUS              PORTS                                  NAMES
b52ee9180210        kindest/node:v1.15.3   "/usr/local/bin/entr…"   14 minutes ago      Up 13 minutes       35507/tcp, 127.0.0.1:35507->6443/tcp   kind-control-plane

$ kubectl get nodes

NAME                 STATUS   ROLES    AGE   VERSION

kind-control-plane   Ready    master   17m   v1.15.3

But this is a single node cluster. But if you want to create a multi-node HA cluster we need to do the following settings.

First, delete the current cluster.

$ kind delete cluster
Deleting cluster "kind" ...
$KUBECONFIG is still set to use /home/ajeesh/.kube/kind-config-kind even though that file has been deleted, remember to unset it
$ unset KUBECONFIG
This will delete the kubeconfig file on your .kube folder.
/.kube$ ls
cache  http-cache

 $ docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES

A cluster with 3 control-plane nodes and 3 workers

$ cat multi-node-kind.yml
kind: Cluster
apiVersion: kind.sigs.k8s.io/v1alpha3
nodes:
- role: control-plane
- role: control-plane
- role: control-plane
- role: worker
- role: worker
- role: worker
~$ kind create cluster --config multi-node-kind.yml
Creating cluster "kind" ...
 ✓ Ensuring node image (kindest/node:v1.15.3) 🖼
 ✓ Preparing nodes 📦📦📦📦📦
 ✓ Configuring the external load balancer ⚖️
 ✓ Creating kubeadm config 📜
 ✓ Starting control-plane 🕹️
 ✓ Installing CNI 🔌
 ✓ Installing StorageClass 💾
 ✓ Joining more control-plane nodes 🎮
 ✓ Joining worker nodes 🚜
Cluster creation complete. You can now use the cluster with:
export KUBECONFIG="$(kind get kubeconfig-path --name="kind")"
kubectl cluster-info

I have some issue with resources so I have reduced worker node to 1 from 3

$ kubectl get nodes
NAME                  STATUS   ROLES    AGE     VERSION
kind-control-plane    Ready    master   2m20s   v1.15.3
kind-control-plane2   Ready    master   106s    v1.15.3
kind-worker           Ready       46s     v1.15.3
:~$ docker ps
CONTAINER ID        IMAGE                          COMMAND                  CREATED             STATUS              PORTS                                  NAMES
a0e52dd3effa        kindest/node:v1.15.3           "/usr/local/bin/entr…"   4 minutes ago       Up 3 minutes                                               kind-worker
2a6c8833c3cb        kindest/node:v1.15.3           "/usr/local/bin/entr…"   4 minutes ago       Up 3 minutes        35213/tcp, 127.0.0.1:35213->6443/tcp   kind-control-plane2
4e38366ad4a7        kindest/haproxy:2.0.0-alpine   "/docker-entrypoint.…"   4 minutes ago       Up 4 minutes        37331/tcp, 127.0.0.1:37331->6443/tcp   kind-external-load-balancer
8a0ce1959722        kindest/node:v1.15.3           "/usr/local/bin/entr…"   4 minutes ago       Up 3 minutes        36145/tcp, 127.0.0.1:36145->6443/tcp   kind-control-plane

:~$ kind get nodes
kind-worker
kind-control-plane2
kind-external-load-balancer
kind-control-plane
~$ kubectl -n kube-system get all
NAME                                              READY   STATUS    RESTARTS   AGE
pod/coredns-5c98db65d4-hmrxc                      1/1     Running   0          4m31s
pod/coredns-5c98db65d4-vgj9w                      1/1     Running   0          4m31s
pod/etcd-kind-control-plane                       1/1     Running   0          3m36s
pod/etcd-kind-control-plane2                      1/1     Running   0          4m12s
pod/kindnet-7754r                                 1/1     Running   1          4m13s
pod/kindnet-9c4rt                                 1/1     Running   1          4m31s
pod/kindnet-b2td4                                 1/1     Running   1          3m13s
pod/kube-apiserver-kind-control-plane             1/1     Running   0          3m36s
pod/kube-apiserver-kind-control-plane2            1/1     Running   0          4m12s
pod/kube-controller-manager-kind-control-plane    1/1     Running   1          3m58s
pod/kube-controller-manager-kind-control-plane2   1/1     Running   0          3m58s
pod/kube-proxy-c628w                              1/1     Running   0          4m13s
pod/kube-proxy-p9787                              1/1     Running   0          4m31s
pod/kube-proxy-zf6pm                              1/1     Running   0          3m13s
pod/kube-scheduler-kind-control-plane             1/1     Running   1          3m58s
pod/kube-scheduler-kind-control-plane2            1/1     Running   0          4m12s
NAME               TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)                  AGE
service/kube-dns   ClusterIP   10.96.0.10           53/UDP,53/TCP,9153/TCP   4m46s
NAME                        DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR                 AGE
daemonset.apps/kindnet      3         3         3       3            3                                   4m43s
daemonset.apps/kube-proxy   3         3         3       3            3           beta.kubernetes.io/os=linux   4m45s
NAME                      READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/coredns   2/2     2            2           4m46s
NAME                                 DESIRED   CURRENT   READY   AGE
replicaset.apps/coredns-5c98db65d4   2         2         2       4m31s