Building Ansible inventories

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Welcome to the guide to building Ansible inventories. An inventory is a list of managed nodes, or hosts, that Ansible deploys and configures. This guide introduces you to inventories and covers the following topics:

• Creating inventories to track a list of servers and devices that you want to automate.

• Using dynamic inventories to track cloud services with servers and devices that are constantly starting and stopping.

• Using patterns to automate specific sub-sets of an inventory.

• Expanding and refining the connection methods Ansible uses for your inventory.

• How to build your inventory
  • Inventory basics: formats, hosts, and groups
  • Passing multiple inventory sources
  • Organizing inventory in a directory
  • Adding variables to inventory
  • Assigning a variable to one machine: host variables
  • Defining variables in INI format
  • Assigning a variable to many machines: group variables
  • Organizing host and group variables
  • How variables are merged
  • Connecting to hosts: behavioral inventory parameters
  • Inventory setup examples
• Working with dynamic inventory
  • Inventory script example: Cobbler
  • Other inventory scripts
  • Using inventory directories and multiple inventory sources
  • Static groups of dynamic groups
• Patterns: targeting hosts and groups
  • Using patterns
  • Common patterns
  • Limitations of patterns
  • Pattern processing order
  • Advanced pattern options
  • Patterns and ad-hoc commands
  • Patterns and ansible-playbook flags
• Connection methods and details
  • ControlPersist and paramiko
  • Setting a remote user
  • Setting up SSH keys
  • Running against localhost
  • Managing host key checking
  • Other connection methods