DevOps Batch June 2023 – Ansible

What is Ansible?
=========================
	Config mgmt tool for servers

PLAN -> Dev -> Ana -> Build -> UT -> PACK -> Archive -> Dep2QA -> AT -> CC
							Ansible

Config
		Server(S)
	release
		Ansible -> CMD -> FREE
		Tower  - UI -> PAID - Support
		AWX - UI - FREE - nO support
	Python
	From Redhat
==============================
Why Ansible?
===================================
		Bash	 - Windows?
		PS - Linux?

		Python 
			Easy to learn, extend, test, debug, share
		DSL

		Ideompotent
		1 ------- 1 mins
		10 ------- 10 mins
	===============================
		3 changes	- 3 mins
==============================================
Other - chef - pupppet - salt - cf
=======================================================
How ansible works?
==============================================

Human -> ACS -------> ARS

	Linux		any
	ansible 	nR
	--------------------

			Linux -- SSH
			Windows - WInrm

	Python		Linux - Python
			Wndows - PS3.0 , DOTNET4.5
====================================================
What is the component in ACS
======================================
Ansible
	Executables
	Module		- its a Python Code, which run in ARS with param providers
				4000+ Modules + 1000 roles
	Plugins		- its a Python Code, which run in ACS & add a featute of Ansible
	Config		- a file which has param to override behaviours of Executables

Inventory
	a file which contains a IP add of ARS
			group

Playbook
	a yaml file which contains
	
	hosts: localhost OR group name mentioned in Inventory OR all
	tasks:
		module1 and its param
		module2 and its param
		module2 and its param
========================================================

COPY a file in 1 machine
----------------------
cmd 	script?

ansible adhoc command
============================

Project 
Setup a webserver..

Psucode
Step 1 - Install apache2 server in ubuntu		apt name=apache2	state=name
Step 2 - Copy index.html to /var/www/html/index.html	copy src=index.html	dest=/var/www/html/index.html
Step 3  - Start a Process of Apache2			service 	name=apache2 state=started

======================================


ansible localhost -m apt -a"name=apache2 state=present"
ansible localhost -m copy -a"src=index.html dest=/var/www/html/index.html"
ansible localhost -m service -a"name=apache2 state=started"

ansible all -i inventory -m apt -a"name=apache2 state=present" -u ubuntu --key-file=node.pem -b
ansible all -i inventory -m copy -a"src=index.html dest=/var/www/html/index.html"  -u ubuntu --key-file=node.pem -b
ansible all -i inventory -m service -a"name=apache2 state=started"  -u ubuntu --key-file=node.pem -b


ansible web -i inventory -m apt -a"name=apache2 state=present" -u ubuntu --key-file=node.pem -b
ansible web -i inventory -m copy -a"src=index.html dest=/var/www/html/index.html"  -u ubuntu --key-file=node.pem -b
ansible web -i inventory -m service -a"name=apache2 state=started"  -u ubuntu --key-file=node.pem -b

===================================================
How to write a playbook




Playbook
	a yaml file which contains
	
	hosts: web
	tasks:
		module1 and its param
		module2 and its param
		module2 and its param




---
- name: Update web servers
  hosts: web

  tasks:
  - name: Install Apache in ubuntu
    ansible.builtin.apt:
      name: "apache2"
      state: latest
  - name: Copy index.html
    ansible.builtin.copy:
      src: index.html
      dest: /var/www/html/index.html
  - name: Starting a Apache Server
    ansible.builtin.service:
      name: "apache2"
      state: started

ansible-playbook -i inventory web.yaml -u ubuntu --key-file=node.pem -b


==================================================================
VARS 		- DONE


Templates
		vars in playbook - inter*
		vars in file used in playbook - no inter*

Handlers






---
- name: Update web servers
  hosts: web
  vars:
    myname: "Rajesh Kumar"

  tasks:
  - name: Install Apache in centos7
    ansible.builtin.apt:
      name: apache2
      state: latest
  - name: Copy index.html
    ansible.builtin.copy:
      src: index.html
      dest: /var/www/html/index.html
  - name: Template index.html
    template:
      src: index.html.j2
      dest: /var/www/html/index-template.html
  - name: Starting a Apache Server
    ansible.builtin.service:
      name: apache2
      state: started




Handlers

---
- name: Update web servers
  hosts: web
  vars:
    myname: "Rajesh Kumar"
    httpport: 8090

  tasks:
  - name: Install Apache in ubuntu
    ansible.builtin.apt:
      name: apache2
      state: latest
  - name: Copy index.html
    ansible.builtin.copy:
      src: index.html
      dest: /var/www/html/index.html
  - name: Starting a Apache Server
    ansible.builtin.service:
      name: apache2
      state: started
  - name: Template for httpd.conf
    template:
      src: ports.conf.j2
      dest: /etc/apache2/ports.conf
    notify:
      - ReStarting a Apache Server

  handlers:
  - name: ReStarting a Apache Server
    ansible.builtin.service:
      name: apache2
      state: restarted

===========================================================================================================
ROLE
==============================================================
a dir sructure
-------------------------
	for managing following
		- tasks
		- vars
		- template
		- file
		- handlers


site.yaml

---
- name: Update web servers
  hosts: web

  roles:
  - web