HAproxy + AWS + Ansible

Deploy Load Balancer on AWS through ANSIBLE!

What is Load Balancing?

Load Balancing is a process that is used to uniformly route the request of users/clients to the different servers that are available for use i.e. to the servers that are currently in working condition. In simpler words, load balancing is a process of balancing the load on different servers.

The Task We are going to perform is :

♦️ Provision EC2 instances through ansible.

♦️ Retrieve the IP Address of instances using the dynamic inventory concept.

♦️ Configure the web servers through the ansible role.

♦️ Configure the load balancer through the ansible role.

♦️ The target nodes of the load balancer should auto-update as per the status of web servers.

We are going to create environment like this :

So, Let’s Get started…

Firstly, We have to install Boto/Boto3 library in the controller node(CN) that will help us to create, configure, operate, and maintain AWS services through the Python scripts.

pip3 install boto

Create one playbook to launch the instances in AWS → I have used 2 webservers from which loadbalancer will be routing the traffic.)

1-Loadbalancer and 2-Webserver ---> Managed Nodes(MN)

Run the Playbook → ansible-playbook instance.yml

All Nodes are launched Successfully.

Now, We have to retrieve the Public IP of the instances dynamically in the inventory file.

So, Download the ec2.py and ec2.ini files.

 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

To make the files executable, change the file permissions.

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

Update the first line of the ec2.py file, which will tell the exact location of interpreter to execute the python script.

#!/usr/bin/python3

Now, Provide the AWS access credentials like this :

AWS_ACCESS_KEY_ID=XXXXXXXXXXXXX
AWS_SECRET_ACCESS_KEY=XXXXXXXXX

We have fetched Public IP of MN → ansible all — list-hosts

Create two ansible roles one for LoadBalancer and another for Webservers.

ansible-galaxy init loadbalancer  ---> role created for loadbalancer 
ansible-galaxy init webserver     ---> role created for webserver

Also We, need to set the path of role inside ansible configuration file (ansible.cfg)

roles_path=/Ansible_Task_3

Now, we can write the tasks inside tasks/main.yml file to configure the loadbalancer.

- name: INSTALL HAPROXY SERVER
  package:
          name: haproxy
          state: present
- name: COPY HAPROXY CONF FILE TO LB
  template:
          dest: “/etc/haproxy/haproxy.cfg”
          src: “haproxy.cfg.j2”
  notify: LBrestart
- name: START THE SERVICE
  service:
          name: haproxy
          state: started

write handlers inside inside handlers/main.yml

- name: LBrestart
  service:
          name: haproxy
          state: restarted

First install haproxy at the Controller Node

yum install haproxy -y      ---->  It will install haproxy

Inside the configuration file of haproxy (haroxy.cfg.j2) We need to change the port number binding, to which our client is going to request for the webpages. You can use any port No. Here, I have used Port 8080.

Also We need to provide the public IP of all the instances with Port 80 . We have used Jinja Template to extract the hostname of each ec2 instances dynamically by using the predefined variable “tag_Name_web”.

backend app
    balance    roundrobin
{% for i in groups[‘tag_Name_web’] %}
    server app{{ loop.index }} {{ i }}:80  check
{% endfor %}

Copy the haproxy.cfg.j2 file and paste it into the /Ansible_Task_3/loadbalancer/templates directory.

Now, Write the tasks inside tasks/main.yml file of webserver role to configure the Webservers.

- name: INSTALL HTTPD PACKAGE
  package:
          name: httpd
          state: present
- name: COPY THE FILE
  template:
          dest: "/var/www/html/"
          src: "index.html"
  notify: restart
- name: START THE SERVICE
  service:
          name: httpd
          state: started

Now, We can wirte the main playbook to run all the tasks.

- hosts: tag_Name_LoadBalancer
  roles:
          - role: loadbalancer
- hosts: tag_Name_web
  roles:
          - role: webserver

We are good to run the playbook now!

ansible-playbook setup.yml

Check the working of your Loadbalancer by using its Public IP and its Port No.

13.127.23.104:8080      ---> This is for my case

The final output will look like this :

Finally, Our LoadBalancer has been deployed successfully.🤘

Thank You For Reading!😇