2.4 KiB
Ansible Modules
Introduction
Ansible ships with a number of modules (called the 'module library')
that can be executed directly on remote hosts or through playbooks
. Users can also
write their own modules. These modules can control system resources,
like services, packages, or files (anything really), or handle executing
system commands.
Let's review how we execute three different modules from the command line:
ansible webservers -m service -a "name=httpd state=running"
ansible webservers -m ping
ansible webservers -m command -a "/sbin/reboot -t now"
Each module supports taking arguments. Nearly all modules take
key=value
arguments, space delimited. Some modules take no
arguments, and the command/shell modules simply take the string of the
command you want to run.
From playbooks, Ansible modules are executed in a very similar way:
- name: reboot the servers
action: command /sbin/reboot -t now
Version 0.8 and higher support the following shorter syntax:
- name: reboot the servers
command: /sbin/reboot -t now
All modules technically return JSON format data, though if you are using the command line or playbooks, you don't really need to know much about that. If you're writing your own module, you care, and this means you do not have to write modules in any particular language -- you get to choose.
Modules are idempotent, meaning they will seek to avoid changes to the system unless a change needs to be made. When using Ansible playbooks, these modules can trigger 'change events' in the form of notifying 'handlers' to run additional tasks.
Let's see what's available in the Ansible module library, out of the box:
Writing your own modules
See moduledev
.
contrib
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User contributed playbooks, modules, and articles
examples
-
Examples of using modules in /usr/bin/ansible
playbooks
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Examples of using modules with /usr/bin/ansible-playbook
moduledev
-
How to write your own modules
api
-
Examples of using modules with the Python API
- Mailing List
-
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-
#ansible IRC chat channel