Ansible Wechat Account Ansible Meetup Shanghai August 17th - - PowerPoint PPT Presentation

Ansible Wechat Account

Ansible Meetup Shanghai August 17th

wiredcraft.com ansible.com

Introduction

What is Ansible?

• Ansible.com
• Ansible on GitHub
• Python based
• Easy to extend
• Agent-less
• Gaining momentum
• Very fast learning

curve

• Easy to get started

Similar Tools

• salt-stack: python based, server / agent

(minions)

• puppet: ruby based, server/agent - harder
• chef: ruby based, server/agent - harder
• capistrano: ruby based, more focused toward

deployment workflow

Install and Configuration

Install

• either through your package manager, yum / apt-get
• or better through pip install ansible for the latest versions

Configuration

• environment variables
• ansible.cfg in current folder, home dir or /etc/ansible

Latest version are "preferred" as Ansible evolves very quickly with bug fixes and new features (4 months ago newest release and daily pull request)

Concepts

Ansible Concepts

YAML

• used everywhere; to list tasks, handlers, variables, etc.
• it's the easiest way to have a structured yet reader friendly file

structure (e.g. compared to json) Modules

• atomic operations
• manage idempotence
• many are core, lots are community, covers from cloud service (aws), to

lineinfile, to file, to ...

Ansible Concepts

Playbook

• sequential list of operation
• collection of tasks, handlers

Tasks / Handlers

• tasks: has a name, executes a module action, completes with

either success / failure / skipped

• handlers: "sleeping" tasks that can be invoked by a task upon

completion (e.g. when config file change, restart service)

Ansible Concepts

Variables

• host_vars - host specific variables
• group_vars - group specific variables
• file vars - external file that can be used to load some variables

(syntax -e "@filename.yml")

• vars registration - one can register variable during the execution of a

playbook for future use Inventory

• collection of hosts / groups

Tool Belt CLI

Tool Belt

Ansible

• used to run simple modules
• ansible all -i hosts -m ping

Ansible-playbook

• used to execute a playbook
• ansible-playbook -i hosts playbook.yml

Tool Belt

Ansible-vault

• used to access and load secrets

Ansible-galaxy

• used to search, fetch roles
• ansible-galaxy install user.roles fetch and install a role

globally (in `/etc/ansible/roles`)

• ansible-galaxy install -r roles.txt -p roles fetch

and install roles defined in roles.txt file (similar to requirements.txt) and save in roles folder

Roles / Galaxy

• Community driven collection of roles at http://

galaxy.ansible.com

• Roles are collection of tasks / handlers used to

tackle larger set of tasks - e.g. setup, install, configure nginx and the vhosts

Questions?

Live Demo

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