Ansible | Getting Started

Installation

Install Python 3

Install Ansible

<pre class="EnlighterJSRAW" data-enlighter-group="" data-enlighter-highlight="" data-enlighter-language="shell" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-theme="" data-enlighter-title="">pip install ansible

Setup virtual machines

In this example, we use Vagrant. But using docker is also a good choice

Create Vagrantfile

Change IP Address and Hostname for each virtual machine

<pre class="EnlighterJSRAW" data-enlighter-group="" data-enlighter-highlight="" data-enlighter-language="generic" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-theme="" data-enlighter-title="">Vagrant.configure("2") do |config|
  config.vm.box = "hashicorp/bionic64"
  config.vm.network "public_network", ip: "172.16.2.191", bridge: "en0: Ethernet"

  config.vm.synced_folder "./data", "/DATA"
  config.vm.hostname = "host1"
end

Start virtual machine

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vagrant ssh

Configure virtual machine

Install required programm sshpass for running ansible commands as root on target machines.

<pre class="EnlighterJSRAW" data-enlighter-group="" data-enlighter-highlight="" data-enlighter-language="shell" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-theme="" data-enlighter-title="">sudo apt-get install sshpass

Setup SSH permissions

Create ssh key

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Add id_rsa_<user>.pub to virtual machines into $HOME/.ssh/authorized_keys

Setup config files

etc/ansible/hosts

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ansible2
ansible3

etc/ansible/ansible.cfg

Create Ansible configuration file in current directory with this content:

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interpreter_python = auto

Ansible searches for configuration files in the following order, processing the first file it finds and ignoring the rest:

1. $ANSIBLE_CONFIG if the environment variable is set.
2. ansible.cfg if it’s in the current directory.
3. ~/.ansible.cfg if it’s in the user’s home directory.
4. /etc/ansible/ansible.cfg, the default config file.

First Test

<pre class="EnlighterJSRAW" data-enlighter-group="" data-enlighter-highlight="" data-enlighter-language="shell" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-theme="" data-enlighter-title=""> ansible -i etc/ansible/hosts all -m ping -u vagrant

Set default Python version on Ubuntu

<pre class="EnlighterJSRAW" data-enlighter-group="" data-enlighter-highlight="" data-enlighter-language="generic" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-theme="" data-enlighter-title="">update-alternatives --install /usr/bin/python python /usr/bin/python3.6 1

Working with Playbooks

Create simple playbook

Create file httpd.yaml

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- hosts: webservers
  remote_user: ansible
  tasks:
  - name: Ensure apache is installed and updated
    yum:
      name: httpd
      state: latest
    become: yes

Run playbook

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Troubleshooting

Allow SSH root login

<pre class="wp-block-preformatted">$ sudo sed -i 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config