The basics

Shreya Chakraborty

Software Engineer

Why Configuration Management?

• Snowflake servers
• Configuration management (CM) is a systems engineering process for establishing and maintaining consistency of a product's performance, functional, and physical attributes with its requirements, design, and operational information throughout its life.(WIKI)

Brief History

• Ansible was released in 2012 by Michael DeHaan

• Ansible, Inc. was the company set up to commercially support and sponsor Ansible. Red Hat acquired Ansible in October 2015

YAML Ain’t MARKup Language

---
- hosts: webservers
 vars:
   http_port: 80
   max_clients: 200

[
 {
   "hosts": "webservers",
   "vars": {
     "http_port": 80,
     "max_clients": 200
   }
 }
]

Basic Playbook Anatomy

Variables

• Inventory variables
• Playbook variables
• Variables from roles and included files
• Command line variables

Facts

• Fact caching
• Dynamic variables - set_fact

http://docs.ansible.com/ansible/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable

Modules, Modules, Modules!!!

Roles

Ansible Vault/Encryption

• specific variables in files
• encrypt entire file

Ansible Command Line 

Idempotency

Why Ansible

• Run commands parallely execution across multiple machines.

• Multiple idempotent 'modules'

• Automatic reporting of task execution.

• Tagging, and restricting tasks.

• Readable syntax , sufficient logic flow and ease-of-variable-managing.

• Composability/modular

• Agentless architecture

Best Practises

• Use role name prefixes for all variables in roles
• Use Native YAML Syntax
• Use jinja filters instead of conditions
• Use Modules instead of Run Commands
• Build custom modules pertaining to your use cases
• Use ansible-vault for sensitive data 

Success Stories

https://stackshare.io/ansible/in-stacks

@shrechak

We are hiring!!!

@Indix