Kubernetes basic setup

kubesetup.md

Kubernetes basic setup

Huge thanks to Ani for showing me this

ON EVERY MACHINE (slaves and master)

Set hostname

nano /etc/hostname # Write your machine's IP

Prepare for kube utils

apt-get update && apt-get install -y apt-transport-https curl

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -

cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF

apt-get update

Install kube utils

apt-get install -y kubelet kubeadm kubectl
apt-mark hold kubelet kubeadm kubectl

Prepare for docker

apt-get install \
	ca-certificates \
	gnupg2 \
	software-properties-common

curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -

apt-key fingerprint 0EBFCD88

sudo add-apt-repository \
	"deb [arch=amd64] https://download.docker.com/linux/debian \
	$(lsb_release -cs) \
	stable"

Install docker

apt-get install docker-ce=18.06.1~ce~3-0~debian

Disable swap

swapoff -a
nano /etc/fstab # Remove swap entry

ONLY ON MASTER

Init kubeadm

IP_MASTER=<your-master-ip>
TOKEN=`kubeadm token generate`

kubeadm init  \
	--pod-network-cidr 10.244.0.0/16 \
	--token $TOKEN \
	--skip-token-print \
	--apiserver-advertise-address $IP_MASTER

As normal (non-root) user in kubeadm

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

ONLY ON SLAVES

kubeadm token create --print-join-command

Produces

kubeadm join <your-master-ip>:6443 \
    --token qv2auc.yppv796dht7q4r1w \
    --discovery-token-ca-cert-hash \
    sha256:9df81aef766ca7d93818bfcf24c00cb1a3413bd148357cce6db7853114a966bd

✨ Your cluster is up and running 🌈

ONLY ON YOUR LOCAL MACHINE (your computer)

Copy config from master

scp root@<your-master-ip>:/home/<your-kube-user>/.kube/config ~/.kube/config

List all nodes and pods

kubectl get nodes
kubectl get pods --all-namespaces

Install flannel (Network plugin)

kubectl apply -f \
    https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

List all pods (now you have flannel pods)

kubectl get pods --all-namespaces

Install dashboard app (this also creates a role for the dashboard but does not bind it)

kubectl apply -f \
    https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

List all pods (now you have a dashboard pod)

kubectl get pods --all-namespaces

Bind kubernetes-dashboard role to cluster-admin role

kubectl create clusterrolebinding \
	kubernetes-dashboard \
	--clusterrole=cluster-admin \
	--serviceaccount=kube-system:kubernetes-dashboard

Create a namespace for an app (optional)

kubectl create namespace staging
kubectl get namespaces # List 'em

Proxy kubernetes API on your localhost (127.0.0.1)

kubectl proxy

Get dashboard token

kubectl -n kube-system describe secret \
		$(kubectl -n kube-system get secrets | \
            grep kubernetes-dashboard | \
            cut -f1 -d ' ') | \
            grep -E '^token' | \
            cut -f2 -d':' | tr -d '\t'

Dashboard URL, you can login with the token (it is local thanks to kubectl proxy)

http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/login

---

Todo

• StorageClass
• Deploy a custom application