Kishor Chavan
Understanding Infrastructure as Code and Configuration Management -Ansible

Understanding Infrastructure as Code and Configuration Management -Ansible

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Kishor Chavan
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5 min read

What's the difference between Infrastructure as Code and Configuration Management?

In the realm of cloud technology, Infrastructure as Code (IaC) and Configuration Management (CM) are inherently entwined. IaC operates through a descriptive blueprint for overseeing infrastructure, covering elements such as networks, virtual machines, and load balancers. Utilizing an IaC model guarantees uniform settings every time it's implemented.

Meanwhile, Configuration Management (CM) plays a vital role in maintaining the uniformity and reliability of a product across its entire lifespan. It focuses on preserving performance, functionality, design, and operational consistency from inception to operation.

Task-01

  1. Read more about IaC and Config. Management Tools

Infrastructure as Code (IaC) orchestrates the management of infrastructure through a descriptive framework, covering elements such as networks, virtual machines, and load balancers. When implemented, an IaC model consistently reproduces an identical environment.

In contrast, Configuration Management (CM) ensures the uniformity of an application's behavior, spanning performance, functional and physical inputs, requirements, overall design, and operations throughout the entire life cycle of the product.

  1. Highlighting Differences with Appropriate Examples

The primary divergence between Infrastructure as Code (IaC) and Configuration Management (CM) lies in their distinct focuses. IaC centers around the management and provisioning of infrastructure through code, emphasizing the automation of components such as virtual machines, networks, and storage in a repeatable and scalable manner.

On the other hand, Configuration Management (CM) dedicates itself to automating the configuration and management of software applications, operating systems, and servers. CM tools are integral in automating tasks such as software package installation, enforcing security policies, and managing system settings.

While IaC primarily addresses the infrastructure layer, defining and automating infrastructure components, CM operates at the application layer, automating configurations and management tasks related to software and servers. Despite these distinct focuses, IaC and CM collaborate seamlessly, empowering teams to efficiently automate and manage their IT infrastructure.

  1. Identifying Common IaC and Config Management Tools

Numerous tools facilitate the implementation of Infrastructure as Code (IaC) and Configuration Management (CM), each offering unique features and capabilities. Some widely adopted tools for IaC include:

  • Terraform: A tool designed for constructing, modifying, and versioning infrastructure securely and efficiently.

  • CloudFormation: An AWS service enabling the definition of infrastructure as code, specifically tailored for AWS environments.

  • Pulumi: A versatile tool allowing the creation, deployment, and management of infrastructure across various clouds, using familiar programming languages.

Similarly, various tools are available for Configuration Management:

  • Chef: A configuration management tool streamlining the automation of software deployment, configuration, and management.

  • Puppet: A configuration management tool facilitating the automation of infrastructure, application, and compliance management.

  • SaltStack: A tool automating the configuration and management of software applications, operating systems, and servers.

  • Ansible: A widely adopted configuration management tool with dual capabilities for infrastructure automation. It employs a declarative language for defining infrastructure and applies to both on-premise and cloud environments.

IaC and CM complement each other, contributing to efficient IT infrastructure automation and management. IaC primarily addresses the infrastructure layer, while CM focuses on the application layer. Notable IaC tools include Terraform, CloudFormation, Ansible, and Pulumi, while common CM tools comprise Chef, Puppet, SaltStack, and Ansible.

What's this Ansible?

Ansible is an open-source automation tool, or platform, used for IT tasks such as configuration management, application deployment, intraservice orchestration, and provisioning.

Task-01

  • Installation of Ansible on AWS EC2 (Master Node) sudo apt-add-repository ppa:ansible/ansible sudo apt update sudo apt install ansible

Solution

Step 1: Created new EC2 instance Ansible-Master.

Step 2: Establish ssh connection and incorporate the Ansible PPA repository into your system via the provided command:

sudo apt-add-repository ppa:ansible/ansible

Step 3: update the package

Step 4: install Ansible on Ansible master instance.

Step 5: verify installation

Task-02

  • read more about Hosts file sudo cat /etc/ansible/hosts ansible-inventory --list -y

Solution:

The Ansible hosts file functions as a configuration roster housing servers or hosts managed by Ansible. Located at /etc/ansible/hosts on the Ansible control node, this file outlines the inventory of manageable hosts. Modifying the hosts file can be done using any text editor. For instance, you can use:

sudo cat /etc/ansible/hosts

Once accessible, insert the IP addresses or hostnames of the desired servers. The format for host entries follows this structure:

[group_name]
host1
host2
host3

In this setup, group_name serves as a custom identifier for the host group, while host1, host2, and host3 represent their respective IP addresses or hostnames. The hosts file accommodates multiple host groups, each with its own set of hosts.

After adding hosts, you can confirm Ansible's inventory of manageable hosts using the ansible-inventory command with the --list and -y options:

ansible-inventory --list -y

This command generates a YAML-formatted list displaying hosts and their attributes, encompassing hostnames, IP addresses, and any other defined variables or group memberships, providing a comprehensive overview of the managed infrastructure.

Task-03

  • Setup 2 more EC2 instances with same Private keys as the previous instance (Node)

  • Copy the private key to master server where Ansible is setup

  • Try a ping command using ansible to the Nodes.

Solution

Step 1: Let's create another 2 instance.

We have used same private key Ansible.KP here.

Step 2: Copy private key from local system to Ansible-Master using scp.

scp -i "Ansible.KP.pem" C:/Users/krcha/Downloads/Ansible.KP.pem ubuntu@ec2-34-222-6-7.us-west-2.compute.amazonaws.com:/home/ubuntu/private_keys/

We could see key has been copied in private_keys folder.

Modify permission of key to 600

Step 3: Configure /etc/ansible/host file with 2 new instance and update key file location.

Verify the configuration ansible-inventory --list -y

Step 4: Perform a connectivity test with Ansible by executing a ping command towards the nodes.

with ansible all -m ping we have pinged to all server listed in /etc/ansible/host file.

We can specifically ping to any server like below

We have pinged here ansible-cluster. I hope this article helpful to understand the concept.

Thanks,

Kishor Chavan

ansibleDevopsAWS