DEV Community: collabnix

Installing Kubernetes with on Container Linux using Kubeadm

collabnix — Tue, 22 Dec 2020 10:38:27 +0000

Installing kubeadm kubectl kubelet

Prerequisite:

Install CNI plugins (required for most pod network):

CNI_VERSION="v0.8.2"
mkdir -p /opt/cni/bin
curl -L "https://github.com/containernetworking/plugins/releases/download/${CNI_VERSION}/cni-plugins-linux-amd64-${CNI_VERSION}.tgz" | tar -C /opt/cni/bin -xz

Install crictl (required for kubeadm / Kubelet Container Runtime Interface (CRI))

CRICTL_VERSION="v1.17.0"
mkdir -p /opt/bin
curl -L "https://github.com/kubernetes-sigs/cri-tools/releases/download/${CRICTL_VERSION}/crictl-${CRICTL_VERSION}-linux-amd64.tar.gz" | tar -C /opt/bin -xz

Copy paste the below snippet one by one in your CLI terminal - This is for both Master and Worker Nodes

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}

RELEASE_VERSION="v0.2.7"
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/${RELEASE_VERSION}/cmd/kubepkg/templates/latest/deb/kubelet/lib/systemd/system/kubelet.service" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service
mkdir -p /etc/systemd/system/kubelet.service.d
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/${RELEASE_VERSION}/cmd/kubepkg/templates/latest/deb/kubeadm/10-kubeadm.conf" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

systemctl enable --now kubelet

Initializing kubeadm - This is only for Master

kubeadm init

Setting up kubeconfig - This is only for Master Node

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

Copying token from kubeadmn init snippet - This you should copy from Master. This you will get from Master node only

kubeadm join <control-plane-host>:<control-plane-port> --token <token> --discovery-token-ca-cert-hash sha256:<hash>

Installing Network Plugin - This is only for Master Node

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

Joining Worker Nodes - This is only for Worker Nodes

kubeadm join --token <token> <control-plane-host>:<control-plane-port> --discovery-token-ca-cert-hash sha256:<hash>

Note:

Please do not run Master node snippet commands on Worker Nodes.

References

Installing Kubernetes on Ubuntu 16.04+, Debian 9+ and HypriotOS v1.0.1 using Kubeadm

collabnix — Tue, 22 Dec 2020 10:34:19 +0000

Pre-requisite

Install Docker using curl -sSL https://get.docker.com/ | sh

Installing kubeadm kubectl kubelet

Copy paste the below snippet one by one in your CLI terminal - This is for both Master and Worker Nodes

sudo apt-get update && sudo apt-get install -y apt-transport-https curl
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
cat <<EOF | sudo tee /etc/apt/sources.list.d/kubernetes.list
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF
sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl
sudo apt-mark hold kubelet kubeadm kubectl

Initialize kubeadm - This is only for Master

kubeadm init

Setting up kubeconfig - This is only for Master Node

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

Copying token from kubeadmn init snippet - This you should copy from Master. This you will get from Master node only

kubeadm join <control-plane-host>:<control-plane-port> --token <token> --discovery-token-ca-cert-hash sha256:<hash>

Installing Network Plugin - This is only for Master Node

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

Joining Worker Nodes - This is only for Worker Nodes

kubeadm join --token <token> <control-plane-host>:<control-plane-port> --discovery-token-ca-cert-hash sha256:<hash>

Note:

Please do not run Master node snippet commands on Worker Nodes.

References

Installing Kubernetes on CentOS 7, RHEL 7 and Fedora 25+ using Kubeadm

collabnix — Tue, 22 Dec 2020 10:16:56 +0000

Installing Kubernetes with Kubeadm on CentOS 7/RHEL 7/Fedora 25+

Installing kubeadm, kubectl & kubelet

Copy paste the below snippet one by one in your CLI terminal - This is for both Master and Worker Nodes

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearch
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
exclude=kubelet kubeadm kubectl
EOF

Setting up SELinux in permissive mode (effectively disabling it)

setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes
systemctl enable --now kubelet

Initialize kubeadm - This is only for Master

kubeadm init

Setting up kubeconfig - This is only for Master Node

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

Copy token from kubeadmn init snippet - This you should copy from Master. This you will get from Master node only

kubeadm join <control-plane-host>:<control-plane-port> --token <token> --discovery-token-ca-cert-hash sha256:<hash>

Installing Network Plugin - This is only for Master Node

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

Join Worker Nodes - This is only for Worker Nodes

kubeadm join --token <token> <control-plane-host>:<control-plane-port> --discovery-token-ca-cert-hash sha256:<hash>

Note:

Please do not run Master node snippet commands on Worker Nodes.

References

Deploy your AWS EKS cluster with Terraform

collabnix — Tue, 22 Dec 2020 08:06:08 +0000

Amazon Elastic Kubernetes Service (Amazon EKS) is a fully managed Kubernetes service by AWS. The purpose of this tutorial is to create an EKS cluster with Terraform.

Pre-requisite:

MacOS
Get an AWS free trial account
Install Terraform v0.12.26

brew install terraform

If you’re running Terraform 0.11, I would suggest to upgrade it to 0.12 ASAP.

Install AWSCLI 2.0.17

brew install awscli

Install AWS IAM Authenticator

brew install aws-iam-authenticator

Install WGET

brew install wget

Install Kubectl

brew install kubernetes-cli

Setting up AWS IAM users for Terraform

The first thing to set up is your Terraform. We will create an AWS IAM users for Terraform.

In your AWS console, go to the IAM section and create a user named “SudoAccess”. Then add your user to a group named “SudoAccessGroup”. Attaches to this group the following rights:

AdministratorAccess
AmazonEKSClusterPolicy

After these steps, AWS will provide you a Secret Access Key and Access Key ID. Save them preciously because this will be the only time AWS gives it to you.

In your own console, create a ~/.aws/credentials file and put your credentials in it:

[default]
aws_access_key_id=***********
aws_secret_access_key=****************************

Creating Config file

cat config
[default]
region=us-east-2

Cloning the Repository

git clone https://github.com/hashicorp/learn-terraform-provision-eks-cluster

You can explore this repository by changing directories or navigating in your UI.

$ cd learn-terraform-provision-eks-cluster

In here, you will find six files used to provision a VPC, security groups and an EKS cluster. The final product should be similar to this:

vpc.tf provisions a VPC, subnets and availability zones using the AWS VPC Module. A new VPC is created for this guide so it doesn’t impact your existing cloud environment and resources.
security-groups.tf provisions the security groups used by the EKS cluster.
eks-cluster.tf provisions all the resources (AutoScaling Groups, etc…) required to set up an EKS cluster in the private subnets and bastion servers to access the cluster using the AWS EKS Module.
On line 14, the AutoScaling group configuration contains three nodes.
outputs.tf defines the output configuration.
versions.tf sets the Terraform version to at least 0.12. It also sets versions for the providers used in this sample.

Initialize Terraform workspace

[Captains-Bay]? >  terraform init
Initializing modules...
Downloading terraform-aws-modules/eks/aws 12.0.0 for eks...
- eks in .terraform/modules/eks/terraform-aws-eks-12.0.0
- eks.node_groups in .terraform/modules/eks/terraform-aws-eks-12.0.0/modules/node_groups
Downloading terraform-aws-modules/vpc/aws 2.6.0 for vpc...
- vpc in .terraform/modules/vpc/terraform-aws-vpc-2.6.0

Initializing the backend...

Initializing provider plugins...
- Checking for available provider plugins...
- Downloading plugin for provider "random" (hashicorp/random) 2.2.1...
- Downloading plugin for provider "local" (hashicorp/local) 1.4.0...
- Downloading plugin for provider "null" (hashicorp/null) 2.1.2...
- Downloading plugin for provider "kubernetes" (hashicorp/kubernetes) 1.11.3...
- Downloading plugin for provider "template" (hashicorp/template) 2.1.2...
- Downloading plugin for provider "aws" (hashicorp/aws) 2.64.0...

Terraform has been successfully initialized!

You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.

If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and remind you to do so if necessary.
[Captains-Bay]? >
Apply complete! Resources: 51 added, 0 changed, 0 destroyed.

Outputs:

cluster_endpoint = https://83AEAE7D9A99A68DFA4162E18F4AD470.gr7.us-east-2.eks.amazonaws.com
cluster_name = training-eks-9Vir2IUu
cluster_security_group_id = sg-000e8af737c088047
kubectl_config = apiVersion: v1
preferences: {}
kind: Config

clusters:
- cluster:
    server: https://83AEAE7D9A99A68DFA4162E18F4AD470.gr7.us-east-2.eks.amazonaws.com
    certificate-authority-data: LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSUN5RENDQWJDZ0F3SUJBZ0lCQURBTkJna3Foa2lHOXcwQkFRc0ZBREFWTVJNd0VRWURWUVFERXdwcmRXSmwKY201bGRHVnpNQjRYRFRJd01EVXpNVEpNWkFneVVBS1hma1pQV2d4OXBWdWFOMHkzeE02ZTdTaUtYNFpTNmhFQzcyK1hrK29Na2tsSlFlQ0J3TT0KLS0tLS1FTkQgQ0VSVElGSUNBVEUtLS0tLQo=
  name: eks_training-eks-9Vir2IUu

contexts:
- context:
    cluster: eks_training-eks-9Vir2IUu
    user: eks_training-eks-9Vir2IUu
  name: eks_training-eks-9Vir2IUu

current-context: eks_training-eks-9Vir2IUu

users:
- name: eks_training-eks-9Vir2IUu
  user:
    exec:
      apiVersion: client.authentication.k8s.io/v1alpha1
      command: aws-iam-authenticator
      args:
        - "token"
        - "-i"
        - "training-eks-9Vir2IUu"
region = us-east-2

Configure kubectl

Now that you’ve provisioned your EKS cluster, you need to configure kubectl. Customize the following command with your cluster name and region, the values from Terraform’s output. It will get the access credentials for your cluster and automatically configure kubectl.

aws eks --region us-east-2 update-kubeconfig --name training-eks-9Vir2IUu
Added new context arn:aws:eks:us-east-2:125346028423:cluster/training-eks-9Vir2IUu to /Users/ajeetraina/.kube/

Troubleshooting:

If you are facing the below error message while running terraform init:

[Captains-Bay]? >  terraform validate

Error: Error parsing /Users/ajeetraina/.aws/learn-terraform-provision-eks-cluster/eks-cluster.tf: At 3:18: Unknown token: 3:18 IDENT local.cluster_name

Then to fix it , you need to update your Terraform version by running

brew upgrade terraform