In today’s fast-paced cloud-driven world, efficient IT automation is crucial for businesses, especially outsourcing companies managing diverse infrastructures. Ansible, a popular automation tool, relies on an inventory—a list of nodes (servers)—to execute automation tasks. But did you know there are two main types of Ansible inventories? Let’s break down static and dynamic inventories, and see why dynamic inventory is a game-changer for modern outsourcing firms.

What is Ansible Inventory?

Ansible Inventory is a file or script that tells Ansible which servers (hosts) to manage. It groups servers for targeted automation, making configuration management, app deployment, and orchestration seamless.

Types of Ansible Inventory

• Static Inventory: Manually maintained files listing all your nodes.
• Dynamic Inventory: Scripts or plugins that automatically fetch your servers from cloud providers or APIs.

Static Inventory: Simple but Manual

A static inventory is typically an INI or YAML file like this

[webservers]
web1.example.com
web2.example.com

[dbservers]
db1.example.com

Pros

• Simple to set up for small or fixed environments.
• Easy to read and edit.

Cons

• Manual updates required for every infrastructure change.
• Prone to errors if servers are frequently added/removed.
• Not suitable for dynamic, scalable environments.

Dynamic Inventory: Automated and Scalable

A dynamic inventory fetches host lists from external sources (cloud APIs, CMDBs, etc.) on demand. For instance, with AWS, your inventory is always up-to-date as Ansible queries EC2 for live servers.

ansible-inventory -i aws_ec2.yml --list

Pros

• Real-time, automatic updates.
• Ideal for scaling environments (cloud, hybrid, multi-region).
• Integrates easily with major cloud providers (AWS, Azure, GCP).

Cons

• Initial setup requires knowledge of plugins/APIs.
• May need credentials or API access.

Why Outsourcing Companies Benefit from Dynamic Inventory

For outsourcing providers managing many client infrastructures, dynamic inventory is critical

• Scalability: Instantly adapts to client changes—no manual edits.
• Accuracy: Reduces risk of outdated or incorrect host lists.
• Efficiency: Frees up IT resources for higher value tasks.

How to Set Up Dynamic Inventory in Ansible

Install Required Plugins
Most plugins come with Ansible, but some need extra packages.

Configure Inventory Source
Example for AWS EC2

plugin: aws_ec2
regions:
  - us-east-1
filters:
  instance-state-name: running

Run Ansible with Dynamic Inventory

ansible-inventory -i aws_ec2.yml --list

Best Practices

• Use static inventory for small, stable environments.
• Use dynamic inventory for cloud, scale-out, or multi-client infrastructures.
• Combine both types if needed—Ansible allows mixed sources.

Conclusion

Understanding and choosing the right Ansible inventory type is key for efficient IT automation, especially in the outsourcing sector. Dynamic inventory empowers your teams to automate at scale, respond rapidly to change, and deliver consistent, reliable services to your clients.