Ansible

Ansible is an open-source automation tool used for automating applications, service orchestration, and server configuration management.

Prerequisites

Before diving into Ansible, installation is necessary. Follow the tutorial on how to install Ansible here:

• Ansible Installation

Features

Ansible provides several tools to facilitate server management:

• OpenSSH: Used for setting up SSH and generating keys for server authentication
• Ad-hoc Commands: Used as alternatives to playbooks for quick and simple tasks
• Playbooks: YAML files containing specific tasks to manage servers, used for complex tasks
• Inventory File: Contains the list of servers grouped by categories for organized management

How It Works

SSH Configuration

Ansible relies on SSH to authenticate and configure servers. While you can use a single SSH key for managing all servers, it is often recommended to use two separate keys:

• One for personal SSH logins
• Another specifically for automation with Ansible

Creation of SSH Keys

SSH is a key aspect that Ansible uses to connect remotely to servers, eliminating the need for credential passwords each time a user logs in.

To create SSH keys for both personal use and automation, follow these steps:

• Personal Key (for interactive SSH/logins):

ssh-keygen -t ed25519 -f ~/.ssh/personal_key -C "your_email@domain.com"

• Ansible Key (for automation tasks):

ssh-keygen -t ed25519 -f ~/.ssh/ansible_key -C "ansible@$(hostname)"

After creating the keys, copy them to the servers using:

ssh-copy-id -i ~/.ssh/ansible_key.pub user@server_ip
ssh-copy-id -i ~/.ssh/personal_key.pub user@server_ip

Replace user@server_ip with the appropriate username and IP address or hostname of your target server.

For more details, see:

• SSH Configuration

Launching a Playbook

Playbooks define the automation logic in a structured way. When you run a playbook, Ansible:

1. Loads temporary modules to the remote server
2. Executes the tasks (e.g., install packages, start services)
3. Removes the modules after execution

For more details on playbooks:

• Ansible Playbook Guide

Ad-hoc Commands

Ad-hoc commands are ideal for executing quick operations without creating a playbook. Examples include reboots, file transfers, and directory management.

To learn more about ad-hoc commands, see:

• Ad-hoc Commands
• Ad-hoc (Ansible Docs)

Server Management

Ansible excels at server management by providing:

• Playbooks: Makes task handover between teams seamless, as all required tasks are documented in playbooks
• Inventory Files: Organizes server IP addresses by groups, making it easy to manage and assign tasks
• SSH Key: Automates authentication, making server access and management more efficient

What If Ansible Becomes Outdated?

If Ansible becomes outdated or no longer maintained, other modern tools can be used for infrastructure automation and server management:

• Chef
• SaltStack
• Pulumi
• Puppet

Each tool has its specific strengths:

Tools	Language	Best Used For
Chef	Ruby	Complex enterprise environments
SaltStack	YAML	Large-scale deployments
Pulumi	Various	Cloud infrastructure and resource management
Puppet	Puppet DSL	Large-scale environments