Install Kubernetes on Bare-metal Arch Linux Using kubeadm

install-k8s-arch.md

Install Kubernetes on Bare-metal Arch Linux Using kubeadm

You can use root to perform following steps until a regular user is indicated

Install Packages that K8s(actually kubeadm) requires

If one of these packages are not presented, kubeadm will report warnings or errors

pacman -S docker ebtables ethtool socat

Install some utility packages we need to cope with files

pacman -S curl wget unzip

Install cfssl and cfssjson

I referenced K8s the hard way repo for this part

curl -o cfssl https://pkg.cfssl.org/R1.2/cfssl_darwin-amd64
curl -o cfssljson https://pkg.cfssl.org/R1.2/cfssljson_darwin-amd64
chmod +x cfssl cfssljson
mv cfssl cfssljson /usr/local/bin/

Start Docker

systemctl enable docker && systemctl start docker

Install CNI

export CNI_VERSION="v0.6.0"
mkdir -p /opt/cni/bin
curl -L "https://github.com/containernetworking/plugins/releases/download/${CNI_VERSION}/cni-plugins-amd64-${CNI_VERSION}.tgz" | tar -C /opt/cni/bin -xz

Install kubeadm, kubelet, kubectl

RELEASE="$(curl -sSL https://dl.k8s.io/release/stable.txt)"

mkdir -p /opt/bin
cd /opt/bin
curl -L --remote-name-all https://storage.googleapis.com/kubernetes-release/release/${RELEASE}/bin/linux/amd64/{kubeadm,kubelet,kubectl}
chmod +x {kubeadm,kubelet,kubectl}

curl -sSL "https://raw.githubusercontent.com/kubernetes/kubernetes/${RELEASE}/build/debs/kubelet.service" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service
mkdir -p /etc/systemd/system/kubelet.service.d
curl -sSL "https://raw.githubusercontent.com/kubernetes/kubernetes/${RELEASE}/build/debs/10-kubeadm.conf" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
systemctl enable kubelet && systemctl start kubelet

Creating the cluster

--pod-network-cidr=10.244.0.0/16 is needed because we will be using Flannel

kubeadm init --pod-network-cidr=10.244.0.0/16

Copy config files to a non-root user

Now we add a non-root user by useradd -m foo (You can name the user whatever you want) Still using the root user, we can move the config file to the non-root user's home folder

mkdir /home/foo/.kube
cp -i /etc/kubernetes/admin.conf /home/foo/.kube/config
chown foo:foo /home/foo/.kube/config

At this point you should be able to use kubectl

su - foo # switch to the non-root user and run kubectl
kubectl get nodes
NAME                 STATUS   ROLES    AGE   VERSION
stephen-arch-linux   Ready    master   31m   v1.12.1

Installing a pod network add-on

We will be using Flannel but there are a few others you can choose from. See K8s Document

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/62e44c867a2846fefb68bd5f178daf4da3095ccb/Documentation/kube-flannel.yml

Once Flannel is up, your cluster is up and running.

Making the master schedulable

kubectl taint nodes --all node-role.kubernetes.io/master-

Accessing your k8s services from outside the cluster

Install an Ingress controller, for instance the NGINX Ingress Controller:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/mandatory.yaml

Dont forget the k8s service(NodePort):

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/provider/baremetal/service-nodeport.yaml

Using the Ingress object you will be able to access your services.

Using local volume as PersistentVolumeClaim

Create a storageClass (this object is not namespaced):

---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

Make it the default one:

kubectl annotate storageclass local-storage storageclass.kubernetes.io/is-default-class=true

For each PersistentVolumeClaim, you will need to manually create a PersistentVolume:

---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-pv
spec:
  capacity:
    storage: 10Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /etc/kubernetes/local
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: beta.kubernetes.io/os
          operator: In
          values:
          - linux

Be sure that the spec.local.path exists on the host.