Dynamic_load_balancer

As soon as the the backend webserver is launched , the load balancer also gets updated with the IP of that new server in the system and establish link with it . Hence the whole system become dynamic . Now we just have to launch a load balancer (using load_balancer.yml playbook) and from then whenever we launch a backend server (using web_server.yml playbook) , it's info would automatically be updated in the load balancer. In this way we can easily scale our system.

Pre-requisites

• Docker (Installation Guide)
• Ansible (Installation Guide)

How to use it

After installing the docker , start the docker engine . If you are working on Centos/RHEL ,use following command

systemctl start docker

Also , if you want to make it permanent i.e as soon as you boot your os ,the service also gets started then use following command

systemctl enable docker

Now , configure your Ansible. You may look at my configuration for reference. Save that config file at /etc/ansible/ansible.cfg location(the location might vary depend on your distro/os).

Also , login to your docker hub repository (if you do not have account then make it first)

docker login

This would cause the on-demand downloading of the container images, so we do not have to download them manually. But if you do not want/can't to login , then downalod the image at your workstation.

Now , provison the load balancer using ansible-playbook

ansible-playbook load_balancer.yml

Note-: Run the above command from the same directory where the file is present otherwise the because of relative path there might be error like file not found.

Now you can launch as many as back-end server you want

ansible-playbook web_server.yml

Note-: The above note apply here too.

If you have done all the above steps intact , then you would have feel the power of the system. Fron now on we do not have to any thing , just launch the backend-server as you want and everything would be done on the fly for you... 😀😀