@ -5,28 +5,38 @@ Ansible is a extra-simple Python API for doing 'remote things' over SSH.
While Func, which I co-wrote, aspired to avoid using SSH and have it's own daemon infrastructure, Ansible aspires to be quite different and more minimal, but still able to grow more modularly over time.
While Func, which I co-wrote, aspired to avoid using SSH and have it's own daemon infrastructure, Ansible aspires to be quite different and more minimal, but still able to grow more modularly over time.
Why use Ansible versus something else? (Fabric, Capistrano, mCollective, Func, SaltStack, etc?) It will have far less code, it will be more correct, and it will be the easiest thing to hack on and use you'll ever see -- regardless of your favorite language of choice.
Principles
Principles
==========
==========
* Dead simple setup
* Dead simple setup
* Super fast & parallel by default
* No server or client daemons, uses existing SSHd
* No server or client daemons, uses existing SSHd
* No additional software required on client boxes
* Everything is self updating on the clients. "Modules" are remotely transferred to target boxes and exec'd, and do not stay active or consume resources.
* Only SSH keys are allowed for authentication
* Only SSH keys are allowed for authentication
* usage of ssh-agent is more or less required
* usage of ssh-agent is more or less required (no passwords)
* plugins can be written in ANY language
* plugins can be written in ANY language
* as with Func, API usage is an equal citizen to CLI usage
* as with Func, API usage is an equal citizen to CLI usage
* use Python's multiprocessing capabilities to emulate Func's forkbomb logic
* use Python's multiprocessing capabilities to emulate Func's forkbomb logic
* all file paths can be specified as command line options easily allowing non-root usage
Requirements
Requirements
============
============
For the server the tool is running from, *only*:
For the server the tool is running from, *only*:
* python 2.6 -- or a backport of the multiprocessing module
* python 2.6 -- or the 2.4/2.5 backport of the multiprocessing module
* paramiko
* paramiko
Inventory file
Inventory file
==============
==============
The inventory file is a required list of hostnames that can be potentially managed by
ansible. Eventually this file may be editable via the CLI, but for now, is
edited with your favorite text editor.
The default inventory file (-H) is ~/.ansible_hosts and is a list
The default inventory file (-H) is ~/.ansible_hosts and is a list
of all hostnames to target with ansible, one per line. These
of all hostnames to target with ansible, one per line. These
can be hostnames or IPs
can be hostnames or IPs
@ -39,9 +49,9 @@ Comamnd line usage example
Run a module by name with arguments
Run a module by name with arguments
ssh-agent bash
* ssh-agent bash
ssh-add ~/.ssh/id_rsa.pub
* ssh-add ~/.ssh/id_rsa.pub
ansible -p "*.example.com" -m modName -a "arg1 arg2"
* ansible -p "*.example.com" -m modName -a "arg1 arg2"
API Example
API Example
===========
===========
@ -67,7 +77,7 @@ Parallelism
Specify the number of forks to use, to run things in greater parallelism.
Specify the number of forks to use, to run things in greater parallelism.
ansible -f 10 "*.example.com" -m modName -a "arg1 arg2"
* ansible -f 10 "*.example.com" -m modName -a "arg1 arg2"
10 forks. The default is 3. 5 is right out.
10 forks. The default is 3. 5 is right out.
@ -89,8 +99,12 @@ Features not supported from Func (yet?)
Future plans
Future plans
============
============
* Dead-simple declarative configuration management using