Ansible Notes of June 2024 Session

Thanks

What is Ansible?

Ansible, it’s a component open-source automation for Configuration Management Tool that use Phyton Code Base

Why do we need ansible?

Its human readable automation no special coding skills to do powerful things can be utilized and shared, so they can get productive quickly and contribute their expertise

How Ansible Works?

Is an open source, command-line for automation software application written in Python, works by connecting to nodes and with small programs in modules with Plugins. The nodes are the target servers, network devices, or any computer that you manage with Ansible
 
Components of Ansible?

Executables Playbooks, Modules, Plugins & Config files

Top 10 Ansible Adhoc commands

Ansible ad hoc commands are one-liner Linux shell commands are quick and easy, and playbooks are like a shell script, a collective of many commands with structure logic

6. Ansible modules are small programs or scripts that Ansible uses to perform specific tasks on remote systems. They are the building blocks that Ansible uses to execute commands, deploy configurations, or manage infrastructure. Modules can be simple (like copying a file or installing a package) or complex (like provisioning cloud resources or configuring network devices).

7. Ansible plugins extend the functionality of Ansible by providing additional capabilities beyond what is offered by default modules and features. It can be categorise as Inventory Plugins, module plugins, Action Plugins, Lookup Plugins, Callback Plugines and Filter Plugins.

8.The Ansible configuration file, often referred to as ansible.cfg, is a central configuration file used to customize and control various aspects of how Ansible behaves when executing tasks and playbooks. 

9. An Ansible playbook is a file or script written in YAML format that defines a set of tasks to be executed against one or more managed nodes (servers or devices) in our infrastructure. Playbooks allow us to automate tasks and configurations, making it easier to manage and orchestrate complex IT environments.

10. Variables (often referred to simply as “vars”) are used to store and manage data that can be reused throughout the playbook. They allow us to parameterize the tasks and configurations, making playbooks more flexible and easier to maintain. 

11. A playbook template typically refers to a pre-defined structure or blueprint for writing Ansible playbooks. This template serves as a starting point or guide, ensuring consistency in playbook structure, organization, and best practices across projects or teams.

12. A playbook template provides a structured starting point that includes predefined sections, best practices, and placeholders to facilitate the writing of Ansible automation scripts which can be reusable.

13. Handlers are a special type of task that are triggered by other tasks within a playbook. They are commonly used to manage services that need to be restarted or have their status refreshed only when necessary, usually after changes have been made.

14. Ansible Galaxy is a hub or repository for finding, sharing, and managing Ansible roles.

15. Roles in Ansible are units of organization that encapsulate tasks, handlers, templates, and other Ansible artifacts in a reusable format. 

What is Ansible?Ansible is an open-source automation tool used for configuration management, application deployment, task automation, and IT orchestration. It simplifies complex tasks, reduces manual efforts, and ensures consistency across IT environments.

Why Do We Need Ansible?Ansible is needed for several reasons:

1. Automation: Reduces manual effort by automating repetitive tasks.
2. Consistency: Ensures consistent configuration across multiple servers.
3. Scalability: Easily manages a large number of servers.
4. Simplicity: Uses simple YAML syntax, making it easy to learn and use.
5. Agentless: Does not require agents on remote hosts, simplifying management.
6. Flexibility: Manages various environments including cloud, virtual, and physical.
7. Integration: Works well with various CI/CD tools for DevOps workflows.

How Ansible Works?Ansible works by connecting to nodes (clients/servers) through SSH (or WinRM for Windows) and then pushing out small programs called “Ansible modules” to these nodes. These modules execute the instructions written in the playbooks (Ansible’s configuration, deployment, and orchestration language). After execution, Ansible removes the modules. It follows an agentless architecture, meaning no software needs to be installed on the nodes being managed.

Components of Ansible

1. Playbooks: YAML files containing a series of tasks to be executed on managed nodes.
2. Modules: Small programs executed by Ansible on remote nodes. Examples include command, file, yum, and service modules.
3. Inventory: Lists of hosts managed by Ansible, organized into groups.
4. Plugins: Extend Ansible’s core functionality (e.g., connection plugins, callback plugins, and lookup plugins).
5. Roles: Predefined collections of tasks and configurations.
6. Tasks: The basic units of action in Ansible, which call upon modules.
7. Handlers: Tasks that are triggered by other tasks.
8. Templates: Files that contain variables to be replaced by actual values when the template is processed.
9. Variables: Used to manage dynamic values and manage configurations.

What is Ansible?
Ansible is a software tool that provides simple but powerful automation for cross-platform computer support.
 
Why do we need ansible
It can configure systems, deploy software, and orchestrate advanced workflows to support application deployment, system updates, and more.
 
How Ansible Works?
Ansible works by connecting to nodes (or hosts) and pushing out small programs—called modules—to these nodes. Nodes are the target endpoints—servers, network devices, or any computer—that you aim to manage with Ansible. Modules are used to accomplish automation tasks in Ansible. 
 
 
Component of Ansible?
 Ansible Adhoc
Ansible Modules
Ansible Plusgins
Ansible Configfile
Ansible Playbook
Playbook Vars
PlaybookTemplate
PlaybookHandlers
Ansible galaxy
Roles

Top 10 Ansible Adhoc commands
ansible all -m ping
ansible all -m setup
ansible all -a ” /bin/echo hello”
ansible all -m copy -a “src=/path/to/local/file dest=/path/to/remote/file” -b
ansible all -m service -a “name=nginx sate=restarted” -b
ansible all -m file -a “path=/path/to/file mode=0646” -b
ansible all -m user -a name=johndoe state=present” -b
ansible all -i inventory -m apt -a”state=latest name=apache2″ -u ubuntu –key-file=node.pem -b
ansible all -i 172.31.40.191, -m apt -a”state=latest name=apache2″ -u ubuntu –key-file=node.pem -b
ansible-playbook -i hosts <your yaml> –tags “install” -vvv

What is Ansible?
#Ansible is an Open Source Software, an Automation Engine. This allows us to manage and control multiple servers from one central location and working via SSH Protocol for UNIX systems and winrm for Windows.
 
Why Ansible?
#Very simple to set up, learn and use, Flexible

How Ansible works? Ansible Architecture?
#Human-readable scripts called command, playbooks to declare the desired state of a system. Ansible connects to local or remote servers via SSH and ensures that the system remains in that state.
Architecture : modules, plugins, inventories, playbooks, APIs
 
How to install Ansbile
# install ansible , package, apache ,python, start service, verify version
 
Component of ACS?
# Inventory,Playbook,Control node,Managed node,Module
 
Ansible Adhoc
# uses the /usr/bin/ansible command-line tool to automate a single task on one or more managed nodes
And execute a quick one-liner in ansible without writing a playbook

Ansible Modules
#Ansible modules are units of code that can control system resources or execute system commands.

Ansible Plugins
#Are pieces of code that extend core Ansible functionality.
 
Ansible Configfile
# configuration file : ansible.cfg for configuring core functionality

Ansible Playbook
# List of task, use for deploy and in YAML format.
 
Playbook Vars
# Uses variables to manage differences between systems. Defining them in a file, passing them at the command line, or registering the return value or values of a task as a new variable.

PlaybookTemplate
#You can create a template for a configuration file, then deploy that configuration file to multiple environments and supply the correct data (IP address, hostname, version) for each environment. You can also use templating in playbooks directly, by templating task names and more.

PlaybookHandlers
#Handlers in Ansible playbooks are used to run specific tasks only when a change occurs on a machine.
handlers:
 – name: ReStarting a Apache Server
   ansible.builtin.service:
     name: apache2
     state: restarted

Ansible galaxy
#Command to manage Ansible roles and collections.

Roles
#
Ansible Roles are expressed in YAML used to write configuration files. When a role is included in a task ,Ansible looks for a main.yml file :
Role/
common/
Tasks/
main.yaml
second.yaml
Vars/
main.yaml        
Default/
main.yaml        
Files/
index.html
modify.sh
Templates/
ntp.conf.j2
Handlers/
main.yaml