Overview

This repository is used as a good start point for infrastructure development. It contains basic roles and describes workflow to create solid solution.

The mastery of the ensemble is determined by the quantity and quality of plays performed. Repertory is created to comprise everything needed for server infrastructure of any level and complexity.

Basic principles

• Playbook per application
• All variables should be defined in environments' vars files

Directory structure

• environments/ - root directory for environments
  • environment_dir/ - directory containing vars and hosts per environment
    • group_vars/ - variables defined per group
    • host_vars/ - variables defined per host
    • play_vars/ - variables defined per play in playbooks
    • inventory_file - inventory file with hosts related to the environment
• molecule/ - molecule v2 configuration
  • resources/ - shared among molecule scenarios resources
  • scenario_name/ - specific molecule scenarios divided by platform, default - docker containers
• playbooks/ - directory for playbooks, playbook per application
• roles/ - custom roles
• ansible.cfg - config for ansible
• requirements.txt - python requirements
• requirements.yml - ansible playbooks' requirements
• site.yml - playbook containing every app in infrastructure

What goes where

Variables

• All variables should be defined per environment
• The precedence order can be seen at http://docs.ansible.com/ansible/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable
• Try to use only next places to define a variable:
  • Environment host_vars
  • Environment group_vars
  • Environment play_vars
• Avoid setting variable in playbooks

Tasks

• All tasks should be defined in roles

Playbooks

• Playbooks contain only roles, groups of hosts and vars files
• Playbook should contain everything needed for application to start
• Avoid setting variables and tasks in playbooks
• You can use site.yml as the only entrypoint for your configuration

Getting started

Fast start

• Do not forget use Python 2.7 instead of 3.x. Molecule and Ansible doesn't support Python 3.x
• Clone git repo

git clone git@github.com:express42/ansible-repertory.git

• Install the latest release of Vagrant if you will use ansible-repertory with Parallels VMs
• Then install Vagrant plugin for Parallels

vagrant plugin install vagrant-parallels

• Install prerequisites

cd ansible-repertory
ansible-galaxy install -r requirements.yml
pip install -r requirements.txt
touch vault.key

• Run tests

molecule test

Using with your infrastructure

• Remove excessive roles from requirements.yml, python modules from requirements.txt and playbooks
• Make changes to site.yml
• Make changes to vars files in example environment
• Test changes with command

molecule test

• Copy molecule environment to new environment
• Make changes to inventory and vars files
• Run command

ansible-playbook site.yml --inventory-file=./environments/new_environment/inventory

Molecule

molecule list
molecule converge
molecule status
molecule login common
molecule destroy

Testing using Travis-CI

• Fork git repository
• Add repository into Travis-CI
• Push new commits

ToDo

• Update default packages playbook
• Add more playbooks or list recommended ones
• Add base role (as it is in testo)

Known issues

• 'zabbix_url' variable used in playbooks dj-wasabi.zabbix-agent and dj-wasabi.zabbix-server for different purposes
  • Workaround: redefine 'zabbix_url' in play_vars
• API calls in playbook dj-wasabi.zabbix-agent made from several servers can interfere with each other
  • Workaround: make API calls serial
• While using VirtualBox for testing you should change all mentions of interface 'eth0' to 'eth1'

Links

• Ansible documentation
• Molecule documentation
• Vagrant documentation