# Environments and Dynamic Inventory — Ansible: Automate Servers with Playbooks

Source: https://www.geekswithgeeks.com/en/ansible/prod-inventory-dynamic

> Manage staging and production separately and pull hosts from cloud APIs.

## Hosts change; inventory should follow

In the cloud, servers come and go, so hand-edited lists go stale. **Inventory plugins** (for AWS, Azure, GCP, VMware and others) query the provider and group hosts by tags, regions or instance types. A small YAML config file selects the plugin. Keep one inventory per environment and combine with group variables, so the playbook is identical and only the target and data differ. Always run a `--limit` or a check on a small subset first when pointing at a new inventory.

## An AWS EC2 inventory plugin file

Illustrative; needs the `amazon.aws` collection and credentials. File names must end with `aws_ec2.yml`.

```yaml
plugin: amazon.aws.aws_ec2
regions: [ap-south-1]
filters:
  tag:Environment: production
keyed_groups:
  - key: tags.Role
    prefix: role
```

**Quiz:** Why use a dynamic inventory in the cloud?

- [x] Servers change, so the host list should be generated from the provider
- [ ] It removes the need for SSH
- [ ] Static files are illegal
- [ ] It makes playbooks shorter automatically

*Answer:* Servers change, so the host list should be generated from the provider. Generated inventories stay accurate as instances are created and removed.