Ansible Cheat Sheet

Updated 2026-04-29

Ansible is an agentless automation platform that uses SSH and Python to configure systems, deploy applications, and orchestrate complex workflows. Unlike alternatives that require agents, Ansible runs tasks idempotently — meaning repeated executions produce the same result without side effects, a foundational principle for infrastructure as code. Understanding how playbooks, roles, inventory, modules, and collections interact enables you to automate thousands of servers with declarative YAML, not imperative scripts. Modern Ansible practice increasingly uses Execution Environments — containerized control nodes — to ensure consistent, reproducible automation across teams and pipelines.

What This Cheat Sheet Covers

This topic spans 36 focused tables and 296 indexed concepts. Below is a complete table-by-table outline of this topic, spanning foundational concepts through advanced details.

Table 1: Playbook StructureTable 2: Role Directory StructureTable 3: Inventory File FormatsTable 4: Core ModulesTable 5: Idempotency ConceptsTable 6: Variable PrecedenceTable 7: ConditionalsTable 8: LoopsTable 9: Handlers and NotificationsTable 10: Ansible VaultTable 11: FactsTable 12: Templates and Jinja2Table 13: TagsTable 14: Error HandlingTable 15: CollectionsTable 16: Execution StrategiesTable 17: Delegation and Local ActionsTable 18: Dynamic InclusionTable 19: Privilege EscalationTable 20: Asynchronous ExecutionTable 21: Connection TypesTable 22: Ad Hoc CommandsTable 23: Filters and TestsTable 24: Lookup PluginsTable 25: Meta TasksTable 26: Inventory PatternsTable 27: Check and Diff ModesTable 28: Ansible GalaxyTable 29: Configuration PrecedenceTable 30: Debugging TechniquesTable 31: Register VariablesTable 32: Magic VariablesTable 33: Callback PluginsTable 34: Execution EnvironmentsTable 35: Testing ToolsTable 36: Network Automation

Table 1: Playbook Structure

Element	Example	Description
Play definition	`- name: Deploy app` `hosts: webservers` `become: true`	• Defines the target hosts and play settings • each playbook contains one or more plays.
Tasks list	`tasks:` `- name: Install nginx` `apt: name=nginx state=present`	• Lists the modules to execute in order • tasks run sequentially on each host by default.
Handlers section	`handlers:` `- name: Restart nginx` `service: name=nginx state=restarted`	• Defines tasks triggered by notifications • executed once at end of play even if notified many times.
Variables (vars)	`vars:` `app_port: 8080` `db_host: prod-db.local`	• Stores key-value pairs scoped to the play • accessible in tasks and templates via Jinja2 syntax.

Table 1: Playbook Structure

Element	Example	Description
Play definition	`- name: Deploy app` `hosts: webservers` `become: true`	• Defines the target hosts and play settings • each playbook contains one or more plays.
Tasks list	`tasks:` `- name: Install nginx` `apt: name=nginx state=present`	• Lists the modules to execute in order • tasks run sequentially on each host by default.
Handlers section	`handlers:` `- name: Restart nginx` `service: name=nginx state=restarted`	• Defines tasks triggered by notifications • executed once at end of play even if notified many times.
Variables (vars)	`vars:` `app_port: 8080` `db_host: prod-db.local`	• Stores key-value pairs scoped to the play • accessible in tasks and templates via Jinja2 syntax.