What is Ansible ?

Ansible is an open-source configuration management, software provisioning and application deployment tool that makes automating your application deployments and IT infrastructure operation very simple. It is an agentless solution and easy to configure unlike other automation tool like Puppet or Chef

Installation

Ansible rely on SSH and Python to do all automation and so you only need to install Ansible on the control node and make sure that OpenSSH and Python is installed on both the control (Where the Ansible is install) and the node (host which needs to be configure). When configuring network equipments, there is another way to configure node since it isn’t possible to install python (Python 3 recommended) on these host.

Here are some way to install Ansible :

• via PIP
• via binary
• via repository
• docker

PIP

sudo apt install python3-pip
VERSION=3
pip install ansible==$VERSION
ansible --version

Binary

git clone https://github.com/ansible/ansible.bit
cd ansible
source ./hacking/env-setup
sudo apt install python3-pip
pip install --user -r ./requirements # Module installation for Jinja

Repository

apt-add-repository --yes --update ppa:/ansible/ansible-2.9
sudo apt install ansible
ansible --version

Notes and Recommendations

Even though you can use the root user in Ansible to run Ad-Hoc commands and playbooks, it is not considered a best practice due to the security risks that can arise bys allowing root user ssh access. For this reason, it’s is recommended to create a dedicated Ansible user with sudo privileged on every node and on the manager.

useradd -m aubin
echo "aubin ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers

Now configure the SSH Key to access node without using password

ssh-keygen
ssh-copy-id node[1-x]

Set Python3 as the default interpreter for Ansible. You could link from /usr/bin/python to python3 or you could set the value of ansible_python_interpreter=/usr/bin/python3 in the ansible.cfg file.