INSTALL CLUSTER KUBERNETES

we are going to install kubernetes in a cluster of virtual machines, which were provided with vagrant.

The cluster on two node and manager.

requirements

vagrant

configuring the vitual machines

start the virtual machines

$ vagrant up

Enter in each virtual machine:

$ vagrant ssh manager
$ vagrant ssh node1
$ vagrant ssh node2

disabled swap in each virtual machine of the cluster

$ sudo nano /etc/fstab

comment file

#/dev/mapper/VolGroup00-LogVol01 swap

config selinux in each virtual machine of the cluster

$ sudo nano /etc/selinux/config

SELINUX=disabled

$ sudo yum update

Reboot cluster

$ vagrant reload

verified in the virtual machines that selinux is disabled

$ sestatus

install Kubernetes

in each virtual machine of the cluster

$ sudo yum install -y kubelet kubeadm kubectl
$ sudo su

$ systemctl enable kubelet && sudo systemctl start kubelet

Reboot cluster

$ vagrant reload

before verified ips in each virtual machine

$ ip a

config hosts in each virtual machine of the cluster,

$ sudo nano /etc/hosts

add in file

192.168.1.7 node1
192.168.1.5 node2
192.168.1.8 manager

manager

init cluster kubernetes note: manager requires 2 cpus

$ vagrant ssh manager
$ sudo kubeadm init

join node1 and node2 execute token join on master

kubeadm join 192.168.1.8:6443 --token hxsc56.qc8vn2zbepwxjw59 --discovery-token-ca-cert-hash sha256:2075c05627749013bbd0fcfb044173fcc9f0df451f789cb844c5808d41585a46

To start using your cluster, you need to run the following as a regular user:

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

but if you are root(for this time just run)

$ export KUBECONFIG=/etc/kubernetes/admin.conf

virtualize the network and create roles

$ kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

verifiy

$  kubectl get pods --all-namespaces

node1

$ sudo kubeadm join 192.168.1.8:6443 --token hxsc56.qc8vn2zbepwxjw59 --discovery-token-ca-cert-hash sha256:2075c05627749013bbd0fcfb044173fcc9f0df451f789cb844c5808d41585a46

node2

$ sudo   kubeadm join 192.168.1.8:6443 --token hxsc56.qc8vn2zbepwxjw59 --discovery-token-ca-cert-hash sha256:2075c05627749013bbd0fcfb044173fcc9f0df451f789cb844c5808d41585a46

##validate join nodes in manager

$ kubectl get nodes

##Deployment n manager

$ sudo nano nginx-deployment.yaml

copy


apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2 # tells deployment to run 2 pods matching the template
  template: # create pods using pod definition in this template
    metadata:
      # unlike pod-nginx.yaml, the name is not included in the meta data as a unique name is
      # generated from the deployment name
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80

deployment

$ kubectl apply -f nginx-deployment.yaml

verify deployment

$ kubectl describe deployment nginx-deployment.yaml

view pods

kubectl get pods -l app=nginx

describe pods

kubectl describe pod nginx-deployment-67594d6bf6-bgm8g

Eliminando el deployment

$ kubectl delete -f nginx-deployment.yaml