Ansible Role to Configure Kubernetes Multi Node Cluster over AWS Cloud

let’s direct do the task:

Step 1 : Setup the Ansible configuration file and the inventory. My setup is built upon a dynamic inventory.

Configuration File ansible.cfg :

To setup dynamic inventory for AWS EC2 instances, download ec2.py and ec2.ini file to the controller node using the wget command.

$ wget https://raw.githubusercontent.com/ansible/ansible/stable-2.9/contrib/inventory/ec2.py$ wget https://raw.githubusercontent.com/ansible/ansible/stable-2.9/contrib/inventory/ec2.ini

Install the SDK for AWS that is boto3

$ pip3 install boto3

Make these 2 files executable:

$ chmod +x ec2.py$ chmod +x ec2.ini

Export the following variables along with their values for our particular AWS account, in my case I have chosen region as ap-south-1.

Step 2 : Create 3 roles using the ansible-galaxy init command namely,

• aws_ec2 :- To setup 3 AWS EC2 instances for the multi-node setup.
• k8s_master :- To setup kubernetes master on the instance.
• k8s_worker :- To setup kubernetes worker on the instances.

Step 3 : Create a playbook on the role aws_ec2 with corresponding modules to launch 3 AWS EC2 instances. Run this playbook and after that run the ./ec.py command to verify the setup of dynamic inventory as explained above in step 1.

• Vars file of playbook :

---# vars file for ec2-launch 
image: "ami-089c6f2e3866f0f14"
instance_type: "t2.micro"
region: "us-east-2"
key: testingkey
vpc_subnet_id: "subnet-2321516f"
security_group_id: "sg-07a58bacace819405"
OS_Names:        
    - "K8S_Master"        
    - "K8S_Slave1"        
    - "K8S_Slave2" akey: 'xxxxxxxxxxxxxx'
skey: 'xxxxxxxxxxxxxxxxxxxxxxxxxx'

Playbook for setup :

• Playbook in the tasks directory of our ec2-launch role.

---# tasks file for ec2-launch 
- name: "launching ec2 instances..."  
  ec2:          
          image: "{{ image }}"
          instance_type: "{{ instance_type }}"
          region: "{{ region }}"
          key_name: "{{ key }}"
          wait: yes
          count: 1
          state: present
          vpc_subnet_id: "{{ vpc_subnet_id }}"
          group_id: "{{ security_group_id }}"
          aws_access_key: "{{ akey }}"
          aws_secret_key: "{{ skey }}"
          instance_tags:
                  Name: "{{ item }}"
  loop: "{{ OS_Names }}"

• The main playbook ec2_setup.yml

- hosts: localhost
  roles: 
  — role: “/wstask19/ec2-launch”

• Run the playbook through the role aws_ec2 :

• Status at Web UI after the successful execution of the playbook :

• Now, let’s check the connectivity

Step 4 : Setting up the Multi-Node K8S cluster

• Create 2 roles, one to configure K8s master node and one to configure K8s slave nodes

$ ansible-galaxy role init k8s-master$ ansible-galaxy role init k8s-slaves

• Configuring k8s master

$ vim k8s-master/tasks/main.yml

• The join token for the slave will be displayed on the screen by the debug module.
• Configuring K8s Slaves

$ vim k8s-slaves/tasks/main.yml

• Main Playbook for setting up K8s cluster:

- hosts: ["tag_Name_K8S_Master"]
  roles:
          - name: "config master node.."
            role: "/wstask19/k8s-master"
 - hosts: ["tag_Name_K8S_Slave1", "tag_Name_K8S_Slave2"]
   roles:
          - name: "config slave nodes.."
            role: "/wstask19/k8s-slaves"

• Let’s run the Playbook to configure and set up the Multi Node Cluster

• The playbook ran successfully
• Now, let’s check the status of the cluster by logging in to our EC2 master node.

• The Kubelet service is active and running. ($ Systemctl status kubelet)
• Docker is also active and running. ($ Systemctl status docker)

Let us upload these roles to Ansible Galaxy

• Creating SSH key

$ ssh-keygen

• Read and Copy the SSH key

$ cat <filename>.pub

• Go to Settings in GitHub and click SSH and GPG keys.
• Click on add new and Paste the SSH key.
• Login to GitHub via shell

$ ssh -T git@github.com

• Go to GitHub WebUI and create a repository.
• Initialize the directory and add all the files to the staging area

$ git init
$ git add ./*/*
$ git status

• Commit, Branch, Add your remote origin and finally push your code to the GitHub repository. The files will be added to the repository.

Now,

• Go to your ansible galaxy account and choose my content and click add content.
• Then Choose Import files from GitHub and choose the repository to import
• After a second your roles will be successfully uploaded.
• Follow the same for all three roles.
• And that’s it. The roles are successfully uploaded!

Thanks for reading …….