This document summarizes configuration management tools and introduces Ansible. It notes that Puppet and bcfg2 are pull-based with custom authentication and performance issues, while Ansible is push-based using SSH keys, fast with no daemons. Ansible can be installed with pip and used immediately in one-shot mode or with playbooks for complete configuration management. Playbooks allow defining collections of actions like one-shot mode with notifications. The document concludes that Ansible can go from zero to production in minutes with no custom setup or dependencies.

1. Configuration management finally done right

2. The story so far: Puppet
●slow
●pull-based (dedicated client)
●custom PKI
●huge memory hog, very brittle
●extendable in Ruby only
●hard to share data between nodes
●crazy DSL
●slow

3. The story so far: bcfg2
●acceptable performance
●pull-based (dedicated client)
●custom PKI
●small memory footprint
●extendable in Python
●XML everywhere

4. The future is now: ansible
●no daemons, ever (almost)
●push-based (python is the client)
●ssh keys for authentication
●quite fast and getting faster
●extendable in everything that can write JSON
●fast and furious (<1 year old)

5. Deploying ansible
1. pip install ansible
2. profit!
(almost, some tweaks needed)

6. One-shot mode
ansible webservers -m copy -a
„src=httpd.conf
dest=/etc/apache2/httpd.conf”

7. /etc/ansible/hosts
[webservers]
www[0-100].example.com
[webservers:vars]
app_version=1.23.45
[dbservers]
db0.example.com
db1.example.com

8. Playbooks
●YAML
●collections of actions, mostly like one-shot mode
●notifications (restart apache if config changed)

9. Get shit done
From zero to production in minutes
●no custom authentication
●no client setup
●no daemons
●no external dependencies (DNS, NTP, WTF)
●playbooks very similar to ad-hoc mode
●configuration management or one-off deploys

10. http://ansible.cc/