overview of Ansible

 

overview of Ansible

What is Ansible?

Ansible is an open-source IT automation platform developed by Red Hat, designed to simplify and automate various IT tasks, including configuration management, application deployment, and orchestration. It operates on a agentless architecture, meaning it does not require additional software installations on managed nodes, which can be physical servers, virtual machines, or cloud instances.

Ansible is primarily used by IT professionals, including system administrators and DevOps engineers, who need to manage complex IT environments efficiently. Organizations of all sizes utilize Ansible for its simplicity and effectiveness in automating repetitive tasks.

Ansible automates a wide range of tasks such as:

Provisioning: Setting up servers and services.

Configuration Management: Ensuring systems are configured consistently.

Application Deployment: Installing and updating applications across multiple systems.

Orchestration: Coordinating multiple automated tasks to work together seamlessly.

Ansible can be employed whenever there is a need for automation in IT processes. This includes routine maintenance tasks, deployment of new applications, or scaling infrastructure in response to changing demands. Its use is particularly beneficial in environments that require frequent updates or changes.

Ansible can be run from any machine that acts as a control node, managing one or more managed nodes (the systems being automated). It typically operates over SSH connections, allowing it to manage devices across various environments—be it on-premises servers or cloud-based instances.

The primary reason for using Ansible is to reduce complexity and increase efficiency in IT operations. By automating repetitive tasks, organizations can minimize human error, save time, and allow IT teams to focus on more strategic initiatives rather than manual configurations. Additionally, its simple YAML-based playbook format makes it accessible for users with varying levels of technical expertise.

Ansible operates through the use of playbooks, which are scripts written in YAML that define the desired state of systems. The control node executes these playbooks to send small programs called modules to managed nodes. These modules perform specific tasks and are executed over SSH. Once the tasks are completed, the modules are removed from the managed nodes, ensuring no additional software needs to be installed on them.

Ansible in real-world scenarios

1. Configuration Management

Ansible helps in managing configurations across numerous servers, ensuring that all systems are set up consistently. This includes pushing configuration files and maintaining system states, which is essential for compliance and operational efficiency.

2. Application Deployment

Ansible automates the deployment of applications, making installations, updates, and rollbacks reliable and repeatable. This is particularly useful in DevOps practices where continuous integration and delivery (CI/CD) pipelines are employed.

3. Provisioning

Ansible streamlines the provisioning of infrastructure, whether it be cloud platforms, virtual machines, or bare-metal servers. This includes setting up environments quickly and efficiently, reducing the time required for manual setups.

4. Network Automation

Ansible can automate network management tasks such as configuring routers and switches, monitoring network performance, and ensuring compliance with security policies. This capability helps in building resilient networks that can adapt to changing demands.

5. Security Automation

Ansible orchestrates security protocols by automating the application of security policies across systems. This includes managing firewall rules, user access controls, and monitoring for compliance with security standards.

6. Disaster Recovery

In disaster recovery scenarios, Ansible can automate backups and system restorations, ensuring that critical data is preserved and can be quickly restored in case of failures.

7. Edge Automation

For organizations operating in hybrid cloud environments or utilizing edge computing, Ansible provides a unified platform to manage configurations and deployments across diverse locations.

8. Orchestration

Ansible facilitates orchestration by coordinating multiple automation tasks across different applications and platforms, ensuring that workflows are executed in the correct order to achieve desired outcomes.

For Amazon Linux 2

Launch an Amazon Linux 2 EC2 Instance

Go to the AWS EC2 console and launch a new instance using the Amazon Linux 2 AMI.

Connect to Your Instance

Use SSH to connect to your instance:

ssh -i /path/to/your-key.pem ec2-user@your-instance-ip

Update Your System

Ensure your package manager is up-to-date:

sudo yum update -y

        Install Ansible

You can install Ansible using the Amazon Linux Extras repository:

sudo amazon-linux-extras install ansible2 -y

Verify Installation

Check if Ansible was installed successfully:

ansible --version

Configure SSH Access

Ansible uses SSH to connect to managed nodes. To enable passwordless SSH access from the control node:

Generate an SSH key pair on the control node (if not already done):

ssh-keygen

Copy the public key to the managed node:

ssh-copy-id ansible_user@managed_node_ip

Replace ansible_user with the appropriate username and managed_node_ip with the IP address of the managed node.

Configure Ansible Hosts

Edit the inventory file located at /etc/ansible/hosts to define your managed nodes:

sudo vi /etc/ansible/hosts

Add your node IP addresses or domain names.

ssh config on node

        Open the sshd_config File

Use a text editor to open the SSH daemon configuration file:

sudo vi /etc/ssh/sshd_config

Edit the Configuration for Root Access

    Find the line that specifies PermitRootLogin. It may look like this (line number may vary):

#PermitRootLogin prohibit-password

Change it to:

PermitRootLogin yes

If the line is commented out (preceded by a #), remove the # to uncomment it.

    Enable Password Authentication

Locate the line for PasswordAuthentication, which might be around line 50:

#PasswordAuthentication yes

Change it to:

PasswordAuthentication yes

Again, remove the # if it’s commented out.

Save and Exit

In vi, press ESC, type :wq, and hit Enter to save your changes and exit.

Set a Password for the Root User

Run the following command to set a password for the root user:

sudo passwd root

Restart the SSH Service

For changes to take effect, restart the SSH service:

sudo systemctl restart sshd

Test Your Setup

Run a simple ping command to test connectivity:

ansible all -m ping