How we're using Ansible to manage our infrastructure.

1. Copyright © 2017 Altair Engineering Inc.
Ansible practices
Sebastien Plisson
@splisson
splisson@altair.com
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Innovation Intelligence®

2. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Summary
● Definitions
● Naming conventions
● Directory structure
● Playbooks
● Usage
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3. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Definitions
● Component
○ Part of the infrastructure based on its function: api, web, etc.
● Action
○ Action performed by the playbook: configure, create, update
● Playbook
○ Base script in Ansible called using ansible-playbook
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4. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Definitions (2)
● Variable
○ Defined in yaml files (playbook, var files) or passed on command line (extra-vars)
● Role
○ Collection of tasks, variables, handlers, files, templates that can be called from a playbook or a
role
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5. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Naming conventions
● Playbook
○ <project name>-<component>-<env>-<action>.yml
■ example: todo-api-dev-configure.yml
● Role
○ <author OR project name>.<component OR software>-<action> (optional)
■ Example: todo.api-deploy
● Variable
○ <role name using underscore as separator>-<variable name> : scoping to avoid collision
■ example: todo_api_branch
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6. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Directory structure
● root: playbooks
○ files: shell scripts, files invoked or used directly from playbook
○ group_vars: variables defined for group of nodes
○ inventory: inventory files of nodes, static and dynamic
○ roles
■ <role 1>
■ <role 2>
○ vars
■ <env1>
■ <env2>
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7. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Playbooks
● Contains “Plays”
○ Target a host or multiple hosts (based on the inventory invoked on the command line)
○ Include variables
○ Execute tasks
○ Invoke Roles
● Targeted to build a component in a given environment or for an operation to
execute
● Example: todo-api-staging-install.yml
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8. Ansible practices
Copyright © 2017 Altair Engineering Inc.
Usage
● Playbook includes variables for the environment passed as extra-vars (ie.
target_env) or fixed for the playbook
● Most playbooks only invoke roles
● Sometimes includes pre/post tasks executed before and after roles
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