Notes

What is Ansible?
====================
	Server(S) Config mgt tool
	From Radhat
	Written in py
	Release
		ansible		- cmd
		ansible awx	- gui - free
		ansible tower	- gui - paid

	What config
		Server(S) Config

	What in Server?
		Virtual - HARDWARE
	- file
	- directory
	- services
	- yum - apt
	- bathc - bash
	- users
	- group

Others --> puppet - chef - salt - cfegine


Why Ansible
	manage config of 100s server
	IDEMPOTENCY

		DESIRE		ACTUAL 
		APACHE		YES	- no need to run the script
		CODE		YES - no cha
				NO - make change
	DESIRE			aCTUAL
	apache 80		apache 80
	code

	1st --- 10 Steps -----------	10 STEPS	- 10 mins
	2nd  	1 steps			1 step		- 1 mins
==============================================================
How it works aka Ansible Architecure


HUMAN -> ACS ---> ARS
ACS - Ansible control Server
ARS - Ansible Remote Server

		ACS				ARS
		----------------------------------------
		Linux				ANY
		64 bit

		Ansible				NA

				
		Linux		--SSH--		LINUX
		Linux		--Winrm--	Windows
		
		Linux		--SSH--		LINUX
		py				py


		Linux		--Winrm--	Windows
		py				dotnet + ps 3.0



		Ansible
			Executable(S)	
			Modules		- PY CODE -- RUN IN ARS - based on param
			Plugins		- PY CODE -- RUN IN ACS
			Configfile	/etc/ansible/config
	

cp file dest
===============================================================================
1 Install Ansible 			- DONE

2 Ansible ADHOC Commands		DONE		- 

3 Ansible Inventory			DONE

4. Ansible Playbook

5. Ansible variables - cond 

6. Ansible roles


project -- Setup a webserver
----------------------------------
Step 1 - Install Apache2 in ubuntu	apt	name=apache2 state=present	
Step 2 - copy package file 		copy	src=index.html dest=/var/www/html/
Step 3 - Restart a services		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/"
ansible localhost -m service -a"name=apache2 state=started"



What is inventory
-------------------------
	LIST	of IPS ADD (ARS)
	----
		CMD
		FILE
		SCRIPT

ansible all -i "52.66.80.208,52.66.80.209" -m apt -a"name=apache2 state=present" -u ubuntu -k -b
ansible all -i "52.66.80.208,52.66.80.209"  -m copy -a"src=index.html dest=/var/www/html/"  -u ubuntu -k -b
ansible all -i "52.66.80.208,52.66.80.209"  -m service -a"name=apache2 state=started" -u ubuntu -k -b


52.66.80.208
52.66.80.209
52.66.80.210
52.66.80.211


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

	

52.66.80.208	ansible_user=rajesh ansible_ssh_pass=rajesh12345
52.66.80.209	ansible_user=rajesh ansible_ssh_private_key_file=rajesh.pem	
52.66.80.210	ansible_user=rajesh ansible_ssh_pass=rajesh12345
52.66.80.211	ansible_user=rajesh ansible_ssh_pass=rajesh12345



[web]
52.66.80.208	ansible_user=rajesh ansible_ssh_pass=rajesh12345

[app]
52.66.80.209	ansible_user=rajesh ansible_ssh_private_key_file=rajesh.pem	
52.66.80.210	ansible_user=rajesh ansible_ssh_pass=rajesh12345
52.66.80.211	ansible_user=rajesh ansible_ssh_pass=rajesh12345

[db]
52.66.80.209	ansible_user=rajesh ansible_ssh_private_key_file=rajesh.pem	
52.66.80.210	ansible_user=rajesh ansible_ssh_pass=rajesh12345
52.66.80.211	ansible_user=rajesh ansible_ssh_pass=rajesh12345


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

Here’s a structured and refined version of your Ansible guide with better readability, explanations, and formatting.

What is Ansible?

Ansible is a server configuration management tool developed by Red Hat. It is written in Python and is widely used for automating IT infrastructure.

Ansible Versions

• Ansible CLI → Command-line tool for executing automation tasks.
• Ansible AWX → Open-source GUI for Ansible automation (Free).
• Ansible Tower → Enterprise GUI version of Ansible (Paid).

What Can Ansible Configure?

Ansible can manage and automate various aspects of a server, including:

• Files & Directories – Managing configuration files, system files, and folders.
• Services – Starting, stopping, and configuring services.
• Package Management – Installing/updating packages via yum (Red Hat) or apt (Debian).
• Users & Groups – Managing user accounts and permissions.
• Bash Scripts – Automating batch jobs and shell scripts.
• Infrastructure Components – Virtual machines, networking, cloud infrastructure, etc.

Alternatives to Ansible

Other popular configuration management tools:

• Puppet
• Chef
• SaltStack
• CFEngine

Why Use Ansible?

1. Manage Configurations Across Hundreds of Servers

• Ansible helps maintain configuration consistency across multiple servers.

2. Ensures Idempotency

• Idempotency means Ansible will only make changes when necessary.
• Example:
  • If Apache is already installed, Ansible won’t install it again.
  • If code is missing, Ansible will deploy it.

3. Efficient Execution

• The first execution may involve multiple steps, taking time.
• The second execution only runs required changes, saving time.

Example:

How Ansible Works (Architecture)

Ansible operates using a Control Server (ACS) and multiple Remote Servers (ARS).

Components

Communication Protocols

Ansible Components

Installing Ansible

sudo apt update && sudo apt install -y ansible  # For Ubuntu/Debian
sudo yum install -y ansible                      # For CentOS/RHEL

Running Ansible Ad-Hoc Commands

Ad-hoc commands are used to perform quick tasks without writing playbooks.

Example Commands

# Install Apache on localhost
ansible localhost -m apt -a "name=apache2 state=present"

# Copy an index.html file
ansible localhost -m copy -a "src=index.html dest=/var/www/html/"

# Start Apache service
ansible localhost -m service -a "name=apache2 state=started"

Ansible Inventory

The inventory is a list of target hosts (remote servers) Ansible manages.

Inventory File Examples

Inline Inventory (Command-line)

ansible all -i "52.66.80.208,52.66.80.209" -m apt -a "name=apache2 state=present" -u ubuntu -k -b

File-based Inventory (inventory file)

[web]
52.66.80.208 ansible_user=rajesh ansible_ssh_pass=rajesh12345

[app]

52.66.80.209 ansible_user=rajesh ansible_ssh_private_key_file=rajesh.pem 52.66.80.210 ansible_user=rajesh ansible_ssh_pass=rajesh12345

[db]

52.66.80.211 ansible_user=rajesh ansible_ssh_pass=rajesh12345

Using Inventory File

# Install Apache on all web servers
ansible web -i inventory -m apt -a "name=apache2 state=present" -u ubuntu -k -b

# Copy index.html to all web servers
ansible web -i inventory -m copy -a "src=index.html dest=/var/www/html/" -u ubuntu -k -b

# Start Apache service on all servers
ansible all -i inventory -m service -a "name=apache2 state=started" -u ubuntu -k -b

Ansible Playbook

A playbook is a YAML file that automates multiple tasks.

Example: Web Server Setup

- name: Install Apache Web Server
  hosts: web
  become: yes
  tasks:
    - name: Install Apache2
      apt:
        name: apache2
        state: present

    - name: Copy index.html
      copy:
        src: index.html
        dest: /var/www/html/

    - name: Restart Apache service
      service:
        name: apache2
        state: restarted

Running the Playbook

ansible-playbook -i inventory webserver.yml

Conclusion

Ansible is a powerful automation tool that simplifies server configuration, application deployment, and IT orchestration. Its agentless architecture, idempotency, and ease of use make it one of the top choices for IT automation.

💡 Next Steps:
✅ Learn about Ansible Variables, Conditionals, and Loops
✅ Explore Ansible Roles for reusable automation
✅ Deploy real-world Ansible projects

This refined version improves readability, structure, and clarity while preserving all key information. 🚀 Let me know if you need further modifications!