🎑 Launching Kubernetes Cluster using Ansible on AWS🎑

Vrukshali Torawane
5 min readMar 15, 2021

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πŸ”° What is Kubernetes ?

πŸ‘‰πŸ» Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services, that facilitates both declarative configuration and automation. It has a large, rapidly growing ecosystem. Kubernetes services, support, and tools are widely available.

πŸ”° Why you need Kubernetes and what it can do ?

Containers are a good way to bundle and run your applications. In a production environment, you need to manage the containers that run the applications and ensure that there is no downtime. For example, if a container goes down, another container needs to start. Wouldn’t it be easier if this behavior was handled by a system? That’s how Kubernetes comes to the rescue! Kubernetes provides you with a framework to run distributed systems resiliently. It takes care of scaling and failover for your application, provides deployment patterns, and more. For example, Kubernetes can easily manage a canary deployment for your system.

🎑 Kubernetes provides you with:

πŸ‘‰πŸ» Service discovery and load balancing
πŸ‘‰πŸ» Storage orchestration
πŸ‘‰πŸ» Automated rollouts and rollbacks
πŸ‘‰πŸ» Automatic bin packing
πŸ‘‰πŸ» Self-healing
πŸ‘‰πŸ» Secret and configuration management

πŸ”° What is Ansible?

πŸ“ƒ Ansible is a configuration management system written in Python using a declarative markup language to describe configurations. It is used to automate software configuration and deployment.

πŸ”° Ansible Architecture :

♦️ Ansible Playbooks :

Ordered lists of tasks, saved so you can run those tasks in that order repeatedly. Playbooks can include variables as well as tasks. Playbooks are written in YAML and are easy to read, write, share and understand.

♦️ Inventory :

A list of managed nodes. An inventory file is also sometimes called a β€œhostfile”. Your inventory can specify information like IP address for each managed node. An inventory can also organize managed nodes.

πŸ”° Let’s Begin…

We don’t have any hosts or instances running

1. Launching EC2 Instances using Ansible with dynamic inventory :

>>> Create Role :

ansible-galaxy init ec2

>>> In tasks file :

ec2:
key_name: "{{ key_name }}"
instance_type: "{{ instance_type }}"
image: "{{ image_id }}"
wait: yes
count: "{{ count }}"
# instance_tags:
# name: "sample_os"
vpc_subnet_id: "{{ subnet_id }}"
assign_public_ip: yes
state: present
region: "{{ region }}"
group_id: "{{ sg_group_id }}"
aws_access_key: "{{ aws_access_key }}"
aws_secret_key: "{{ aws_secret_key }}"
instance_tags:
Name: "{{ item }}"
loop: "{{ OS_name }}"

>>> In vars file :

aws_secret_key: "aws_secret_key"
key_name: "testing"
image_id: "ami-038f1ca1bd58a5790"
count: 1
subnet_id: "subnet-52bc140d"
region: "us-east-1"
sg_group_id: "sg-0639b0dd0a69545ea"
instance_type: "t2.micro"
OS_name:
- "K8S_Master"
- "K8S_Node1"
- "K8S_Node2"

>>> In playbook setup.yml :

- hosts: localhost
gather_facts: False
#vars_files: secret.yml
roles:
- name: "EC2 Launch"
role: /root/task23/k8s/ec2/

>>> Run the playbook :

ansible-playbook setup.yml

πŸ‘‰πŸ» Instances launched and hosts file is been updated

2. Setting Up Master Node and Worker Nodes

πŸ‘‰πŸ» In Master Node,

>>> Create Role :

ansible-galaxy init k8s_master

>>> In tasks file :

- name: "Creating Repo for Kubernetes"
copy:
src: kubernetes.repo
dest: /etc/yum.repos.d/kubernetes.repo
- name: "Installing Software"
package:
name: "{{ item }}"
state: present
loop: "{{ package_name }}"
- name: "Starting services"
service:
name: "{{ item }}"
state: started
loop: "{{ package }}"
- name: "Changing driver to systemd"
copy:
src: daemon.json
dest: /etc/docker/daemon.json
- name: "Restart Docker Services"
service:
name: docker
state: restarted
- name: "Pulling Images"
shell: kubeadm config images pull
- name: "Bridge to 1"
shell: echo "1" > /proc/sys/net/bridge/bridge-nf-call-iptables
- name: "kubeadm init"
shell: kubeadm init --pod-network-cidr=10.244.0.0/16 --ignore-preflight-errors=NumCPU --ignore-preflight-errors=Mem
ignore_errors: yes
- name: "Creating .kube directory"
file:
path: $HOME/.kube
state: directory
- name: "Copying file"
shell: cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
- name: "Changing Owner Permissions"
shell: chown $(id -u):$(id -g) $HOME/.kube/config
- name: "Setting up Flannel"
shell: kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
changed_when: False
- name: "Token Creation"
shell: kubeadm token create --print-join-command
register: token
- name: "Printing Token"
debug:
var: token.stdout

>>> In vars file :

package_name:
- "docker"
- "kubelet"
- "kubeadm"
- "kubectl"
- "iproute-tc"
package:
- "docker"
- "kubelet"

πŸ‘‰πŸ» In Worker Nodes,

>>> Create Role :

ansible-galaxy init k8s_nodes

>>> In tasks file :

- name: "Creating Repo for Kubernetes"
copy:
src: kubernetes.repo
dest: /etc/yum.repos.d/kubernetes.repo
- name: "Installing Software"
package:
name: "{{ item }}"
state: present
loop: "{{ package_name }}"
- name: "Starting services"
service:
name: "{{ item }}"
state: started
loop: "{{ package }}"
- name: "Changing driver to systemd"
copy:
src: daemon.json
dest: /etc/docker/daemon.json
- name: "Restart Docker Services"
service:
name: docker
state: restarted
- name: "Bridge to 1"
shell: echo "1" > /proc/sys/net/bridge/bridge-nf-call-iptables
- name: "Using token"
shell: "{{ token }}"

>>> In vars file :

package_name:
- "docker"
- "kubelet"
- "kubeadm"
- "kubectl"
- "iproute-tc"
package:
- "docker"
- "kubelet"

>>> In playbook k8s_setup.yml :

- hosts: "tag_Name_K8S_Master"
roles:
- name: "K8S Master"
role: /root/k8s/k8s_master
- hosts: ["tag_Name_K8S_Node1", "tag_Name_K8S_Node2"]
vars_prompt:
- name: token
prompt: "Enter token :"
private: no
roles:
- name: "K8S_Nodes"
role: /root/k8s/k8s_nodes

>>> Run the playbook :

ansible-playbook k8s_setup.yml

πŸ”° In AWS instance Master Node ,

All the nodes are ready and we can deploy the pods

kubectl get nodes

πŸ‘‰πŸ» Finally on browser ,

http://<master_ip>:<port_no>

πŸ”° GitHub URL :

https://github.com/Vrukshali-26/k8s-setup-using-ansible.git

Finally our Task is completed successfully !!!!πŸ˜„βœŒπŸ»

Thanks for Reading !! πŸ™ŒπŸ»πŸ˜πŸ“ƒ

πŸ”° Keep Learning !! Keep Sharing !! πŸ”°

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