Ansible: A Practical Guide to Configuration Management

Description

You should be able to identify the following points at the ending of this technical article:

• Describe Infrastructure as Code.
• Interpretation of configuration management and the Ansible tool.
• Capable of working with Ansible to automate your infrastructure, including installation, playbook creation, inventory management, and execution.

Tracing the Roots

The concept of configuration management can be traced back to the 1950s, when it was used in the aerospace industry to manage the complex systems and components used in aircraft and missiles. Configuration management principles were further developed and applied in the software industry in the 1960s, as a way to manage the various components and dependencies of software systems.

This practice became more widely recognized as a critical practice in IT in the 1990s, and a number of commercial configuration management tools and services were developed.

Last but not least, the emergence of agile software development and DevOps practices in the 2000s led to a shift towards more automated and continuous approaches to configuration management, including the adoption of tools and practices of infrastructure as code (IaC).

Decoding Infrastructure as code

Infrastructure as code is a practice that allows you to provision¹ and manage² your infrastructure using code and automated tools, rather than manual processes. It enables you to define and manage your infrastructure in a version-controlled, repeatable, and predictable way.

There are two main aspects of IaC:

1- Infrastructure provisioning: The process of setting up and configuring the various hardware and software components that comprise your infrastructure. This includes tasks like initializing your cloud resources or deploying servers, networking equipment, and storage devices as well as installing and configuring operating systems, applications, and services.

You can automate the provisioning of your infrastructure using code and tools such as

• Terraform, operates in Multi-Cloud Environments
• CloudFormation, IaC AWS
• ARM Templates, IaC Microsoft

This allows you to define the desired state of your infrastructure in code, and then use the above automation tools to provision the infrastructure according to the initial specification.

2- Configuration Management: the process of maintaining the configuration of your infrastructure and applications over time. This includes tasks such as applying software updates, modifying system and application configurations, and ensuring that the infrastructure is running smoothly and efficiently.

You can automate the configuration management of your infrastructure using code and tools such as

• Ansible
• Chef
• Puppet

This enables you to define infrastructure and applications in code and then use the above automated tools to keep track of ur infrastructure and ensure that the app is configured as required.

Since we’ve already covered Terraform, today’s article will go over the power of configuration management using one of the well-known, Ansible.

Let’s start by asking the question below.

Why Configuration Management Matters ?

• Correct configuration management is required for any infrastructure to run smoothly. It contributes to the infrastructure’s optimization for performance, availability, and security.

• Proper configuration management lowers the risk of errors and downtime by allowing you to identify and resolve issues before they become major issues. This can help to improve the infrastructure’s reliability and availability, as well as the overall customer experience.

Furthermore, configuration management is critical for adhering to industry standards and regulations. Systems that are properly configured can help to ensure that the infrastructure meets the necessary requirements for data protection, privacy, and other regulatory compliance issues.

Ansible Configuration Management

Automation and configuration management are critical components of modern infrastructure and operations.

Ansible is an open-source configuration management and automation tool that allows you to automate infrastructure and application deployment, configuration, and management. It defines the desired state of your infrastructure and applications using simple, human-readable YAML files, and then uses those files to automatically configure and manage the systems and services.

Ansible is popular because it is simple to use, has a large and active user and developer community, and is highly flexible and extensible. It can be used to automate a wide range of tasks, including software installation and configuration, system and application configuration management, and application and service deployment.

Gains & Perks

Ansible has several advantages for management configuration and automation, which is why I chose it as our primary tool for this technical article.

• Simplicity: Ansible is easy to use and requires little to no coding knowledge. Its simple, human-readable YAML syntax makes it easy to understand and work with, even for those with little experience in programming or automation.

• Flexibility: Ansible is highly flexible and can be used to automate a wide range of tasks across a variety of environments, including cloud, virtualization, and on-premises systems.

• Scalability: Ansible can be used to manage large, complex infrastructure environments with ease. It has support for parallel execution of tasks, which allows you to scale your automation efforts to meet the needs of your infrastructure.

• Strong Community: Ansible has a large and active community of users and developers, which means there is a wealth of knowledge and resources available to help you get started and troubleshoot any issues you may encounter.

• Extensibility: Ansible is highly extensible and can be integrated with a wide range of tools and services, such as cloud platforms, monitoring systems, and ticketing systems. This allows you to customize your automation efforts to meet the specific needs of your organization.

Mechanism

Ansible communicates with your infrastructure and applications via secure SSH connections and API calls. It employs a simple, push-based architecture, which means that the desired configurations and updates are pushed to the target systems and services rather than pulled.

Ansible defines the desired state of the infrastructure and applications using a series of YAML files known as playbooks. The ansible-playbook command is used to execute these playbooks on the target systems, and the changes are applied automatically.

Ansible also includes a number of pre-built modules that can be used to automate a wide range of tasks, including installing and configuring software, managing system and application configurations, and deploying applications and services. These modules can be used to create custom playbooks that are tailored to your specific needs.

A Complete Walkthrough with Ansible

Ansible is a configuration management tool that allows you to automate infrastructure and application deployment and configuration. It functions by connecting to your servers and running tasks on them.

Let’s go over some of the key components you should be aware of before you begin using the tool.

1- Inventory: This is a list of servers that you want to manage with Ansible. It can be a simple text file or a more complex dynamic inventory.

2- Playbooks: These are files that define the tasks that you want ansible to execute on your servers. They are written in YAML and are organized into a series of plays, each of which defines a set of tasks to be executed on a specific group of servers.

3- Modules: These are small programs that are used by ansible to perform specific tasks on your servers. Ansible comes with a large number of built-in modules that cover a wide range of common tasks, such as installing packages, copying files, and creating users.

The Execution with Ansible

To get started with ansible, you will need to have the following components in place:

• A Linux system with ansible installed. You can install ansible on most major Linux distributions using the package manager. Alternatively, you can install it from source or use a standalone installer.

• A list of servers that you want to manage with ansible. This can be a simple text file with a list of hostnames or IP addresses, or a more complex dynamic inventory that retrieves information about your servers from a remote source.

• A user account with SSH access to the servers in your inventory. Ansible uses SSH to connect to and manage your servers, so you will need a user account with the necessary permissions.

Once these components are in place, you can proceed automating your infrastructure and applications.

0- Install Ansible
1- Create an inventory file
2- Write a playbook
3- Execute the playbook

Installation on different OS

Depending on your operating system, I will try to include the necessary requirements. The following are the steps for installing Ansible on various operating systems

Debian/Ubuntu

1- Update the package manager index:

sudo apt update

2- Install the software-properties-common package, which includes the add-apt-repository command:

sudo apt install software-properties-common

3- Add the Ansible repository to your system:

sudo add-apt-repository ppa:ansible/ansible

4- Update the package manager index again:

sudo apt update

5- Install Ansible:

sudo apt install ansible

CentOS/RHEL

Install the EPEL (Extra Packages for Enterprise Linux) repository, which includes Ansible:

sudo yum install epel-release

Install Ansible:

sudo yum install ansible

Fedora

Install the EPEL repository, which includes Ansible:

sudo dnf install epel-release

Install Ansible:

sudo dnf install ansible

MacOS

• To install Ansible on macOS, you can use the pip package manager, which is included with Python.

pip3 install ansible

• If you prefer to install Ansible using the brew package manager, you can do so by running the following command:

brew install ansible

This will install the latest version of Ansible available in the Homebrew package repository.

• You can also install Ansible from the official Ansible release page on GitHub. To do this, download the desired release as a tar archive, extract the archive, and then run the setup.py script to install Ansible.

tar -xf ansible-X.Y.Z.tar.gz
cd ansible-X.Y.Z
python setup.py install

Windows

• Install the Windows Subsystem for Linux (WSL) by following the instructions at.

• Once WSL is installed, follow the instructions for your desired Linux distribution (e.g. Debian/Ubuntu, CentOS/RHEL, Fedora) to install Ansible that are mentioned above.

Automate Your Infrastructure

Once Installed, action time, you first create an inventory of your servers and write one or more playbooks to define the tasks that you want to run. You can then use the ansible command-line tool to execute the playbooks and apply the desired configuration to your servers.

Let’s start by defining our servers. An inventory file is a plain text file that specifies the hosts that Ansible will manage. Here is an example of an inventory file:

# Declare the group of servers that we want to manage
[webservers]
server1.example.com
server2.example.com

# Declare another group of servers
[database]
db1.example.com
db2.example.com

# Declare a group of servers and specify variables for each server
[appserver:vars]
app1.example.com ansible_ssh_user=appuser ansible_ssh_private_key_file=/path/to/private/key
app2.example.com ansible_ssh_user=appuser ansible_ssh_private_key_file=/path/to/private/key

In this example, there are three groups of servers: webservers, databasev, and appserver` .
Each group is specified by a name in square brackets (e.g. [webservers] ). The servers in each group are listed on separate lines.

The appserver group also includes variables that will be used when connecting to the servers in that group. In this case, the ansible_ssh_user and ansible_ssh_private_key_file variables specify the user to log in as and the path to the private key file, respectively.

This is just a basic example, and an inventory file can be much more complex, depending on your needs. For example, you can specify variables for groups or individual servers, nest groups within groups, and use patterns to define groups of servers. You can also specify multiple inventory files and combine them using the -i option when running Ansible commands.

Now playbook time, to install the Apache web server on a group of servers, you could create a playbook like this:

- hosts: webservers
  tasks:
  - name: Install Apache
    yum:
      name: httpd
      state: present

This playbook consists of a single play that targets the inventory’s “webservers” group. The play has a single task that installs the Apache web server package using the yum module.

To run this playbook, you would use the ansible-playbook command, like this:

ansible-playbook -i inventory.txt webserver.yml 

This would run the playbook on each of the servers in the inventory file, installing Apache on each of them. Good job!

Continue learning Ansible and mastering playbooks with Spacelift’s tutorial!

Ansible can also be used to manage users, install software, and deploy applications, among other things. More information and examples can be found in the Ansible documentation

I suggest the Red Hat documentation as well. RedHat provides support and training for ansible, and offers a range of ansible-based products and services that are designed to help organizations automate and manage their infrastructure and applications. These include the Red Hat Ansible Tower platform, which provides a graphical interface and additional tools for managing and orchestrating ansible tasks.

You may like this!

The Takeaway

That’s it, guys! We covered a lot of great topics, starting with the infrastructure as code and focusing on configuration management, as well as playing with one tool, Ansible, of many!

Today, configuration management is a key aspect of DevOps, as it helps organizations to maintain consistent and predictable environments for their applications. By automating the configuration of systems and applications, organizations can ensure that their environments are consistently configured, reducing the risk of errors and downtime.

Further, It is expected that automation tools like Ansible will continue to be important in the field of DevOps. As organizations increasingly adopt cloud-native technologies and agile methodologies for software development, there will be an increased need for automation and consistency in their environments. Adopt DevOps.