How to clean up Kubernetes

Steps to clean up kubernetes 

Follow below steps to clean

kubeadm reset

sudo apt-get -y purge kubeadm kubectl kubelet kube*

sudo apt-get -y autoremove

sudo rm -rf ~/.kube

How to setup Kubernetes cluster in windows using Ubuntu VMs

Setting up Kubernetes cluster in Windows using Ubuntu VMs

Below lists simple steps that can be followed to set up a cluster using ubuntu VMs. You can set it up in any OS. I have windows machine.

1 master+ 2 node deployment

 Prerequisites

• Oracle VM Virtual Box : Download from https://www.virtualbox.org/
• Turn on hardware virtualization support in BIOS Settings. (Hyper V in windows 10 )
• 
  

Create VMs

Create 2 VMs for 1 master with 1 worker node cluster with below requirements

• Version: Ubuntu (64-bit)
• Processor: 2 CPU
• 4 GB RAM
• Network : Select NAT as adapter 1 and Host only adapter as adapter 2

Initial setup on all nodes

1. Turn off swap  using  sudo swapoff -a
            Comment the line with swap in /etc/fstab
             nano /etc/fstab  
2. Add IP address of all nodes in etc/hosts with details of ip address and hostname as below. 

                        

     Note! Above IP addresses are selected by adding a new virtual host adapter as explained in Add new Adapter Interface . It is also possible to use default IP address selected by Virtual Box as below and no need to create a new adapter interface. 

      3. Install docker

                     apt-get update && apt-get install -y docker.io

       4. Install Kubernetes

          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 http://apt.kubernetes.io/ kubernetes-xenial main

           EOF

          apt-get update && apt-get install -y kubelet kubeadm kubectl

      5. Update cgroup-driver 

            nano /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

    Edit kubeadm.conf file and add below variable after the last Environment

           Environment="cgroup-driver=systemd/cgroup-driver=cgroupfs" 

On Master Node

1. kubeadm init --pod-network-cidr=192.168.0.0/16 --apiserver-advertise-address=<IP_Address_of_MasterNode>

eg: kubeadm init --pod-network-cidr=192.168.0.0/16 --apiserver-advertise-address=172.16.0.3

The above command will generate below comments as part of the output

"

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

You should now deploy a pod network to the cluster.Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:  https://kubernetes.io/docs/concepts/cluster-administration/addons/

You can now join any number of machines by running the following on each nodeas root:
kubeadm join 172.16.0.3:6443 --token 1yy5o4.qokxr4wu5t58kxe1 --discovery-token-ca-cert-hash sha256:ca16640bf7de68d2e036dbe08e5097f6246379ffd87c0d08ef8f4e1d83f08fcc "

Save this join command and can be used to add any number of nodes to your cluster.

2. Start the cluster as mentioned in the result of step1

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

3. Join other nodes using the command after logging to worker nodes

kubeadm join 172.16.0.3:6443 --token 1yy5o4.qokxr4wu5t58kxe1 --discovery-token-ca-cert-hash sha256:ca16640bf7de68d2e036dbe08e5097f6246379ffd87c0d08ef8f4e1d83f08fcc

3. Check whether the nodes are running

kubectl get nodes -o wide

Note! The nodes status will be 'NotReady'  as CNI is not yet installed. Proceed to step 4 for that.

4. Install CNI plugin. I have used calico. If your node has multiple interfaces make sure your /etc/hosts has the IP address of all nodes updated as mentioned in the category Initial setup on all nodes. Otherwise calico will pickup IP address of the first interface

kubectl apply -f https://docs.projectcalico.org/manifests/calico.yaml

5. Check whether all pods are running 

watch kubectl get pods --all-namespaces

Recreate Token

If token has expired and want to join new nodes use below command on master node

kubectl create token

kubeadm list token

Use the token listed using the above command to join the new node