This document discusses using Ansible to automate configuration of Raspberry Pi devices. It recommends Ansible because it allows defining playbooks that can configure different devices like Raspberry Pis and cloud servers in the same way, without requiring agents. It provides an example playbook that configures iptables firewall rules on a device. The document also discusses using a Raspberry Pi as a mock server for testing apps, and deploying apps to a Raspberry Pi from source control using tools like Git hooks or Capistrano.

1. Travel with your
mock server
Jorge D. Ortiz-Fuentes
@jdortiz

2. A POWWAU
production

3. Agenda
★ “Problem”
★ A realistic solution
★ Automation insights
★More automation
★Useful
★Q&A

4. First world
problems

5. My first
Raspberry
Pi
A DIY Story

6. No Power Warning
Raspberry Pi ADSL
UPS
Internet
⌁ X
Notification
Ruby
mailer
Email

7. The “problem”
★ I bought another Raspberry Pi
★ Possible uses:
• Learning computer
• Git server
• File downloader
• File server (even ownCloud)
• Rails test environment
• Domotics server
Want them all!

8. A realistic
solution

9. Have them all separately
★Use different SDs
★ Each for its own purpose
★But…

10. But…
★ Isn’t it to burdensome/expensive to create
and maintain all those “disks”?
★Will they be updated when I need them?

11. Automation

12. Automate my
wishes

13. Automation requirements
★ No dependencies (or few): root and ssh. The image can
be used as is
★ No central server
★ No constant updating
★Reusable solution with my cloud servers
★Configuration in VCS
★My own recipes, but lots available
★Better if language is known

14. CM Tools

15. Alternatives
★Docker:Go; container portability, Linux x86
★ PalletOps:Clojure/JVM; targets cloud servers
★ cfengine: C; steep learning curve, agent
★ Puppet: Ruby; agent based, pull, declarative
★Chef: Ruby; agent based, more imperative
★ Ansible: Python; just ssh access, modules for *
★ Fabric: Python; like scripting SSH, deploy apps
★Capistrano: Ruby; like fabric

16. Ansible
★ Python based (but modules in other langs)
★ Agent-less (SSH with public key auth)
★Declarative
★ Idempotent
★ Playbooks are equal for my cloud server and my
raspberry pi (Ubuntu & Raspbian) and even VM.
★ Talks to other devices (like my Mikrotik)

17. Some Ansible
hints

18. Linux before ansible
★Download latest Raspbian
★Copy image to SD with dd (bs=4M)
★ Setup connected to monitor&kbd
(preserve)
★ Extend FS (preserve to use)

19. Hints
★Don’t put everything in a playbook
★ Some basics:
• Update system
• ntp, ssh, tmux
• iptables
• gitolite
• nginx, postgreSQL,…
★ Playbooks available in:
http://galaxy.ansible.com

20. Configure iptables (1)
roles:
- role: iptables
vars:
incomming_rules: [ { proto: tcp,
dport: http },
{ proto: udp,
sport: ntp } ]
outgoing_rules: [ { proto: udp, dport:
bootps } ]

21. Configure iptables (2)
- name: Add temporary IPv4 rules to allow packaged downloads
shell: "{{ item }}"
with_items:
- iptables -A OUTPUT -p tcp --dport http -j ACCEPT
- iptables -A OUTPUT -p tcp --dport https -j ACCEPT
- name: Update apt cache
apt: update_cache=yes
- name: Ensure iptables is installed (debian)
apt: name={{ item }} state=latest
when: ansible_os_family == 'Debian'
with_items:
- iptables
- iptables-persistent
- name: Verify directory exists for iptables rules
file: path={{rules_dir}} owner=root group=root mode=0700 state=directory
- name: Create iptables rules for IPv4 from template and vars
template: dest={{ip4tables_rules_path}} src=etc/iptables/rules.v4.j2 owner=root group=root
mode=0400

22. Can’t automate
anymore, my a**

23. Deploy (rails)
apps

24. Git hooks
★Bare repo
★Git hook
• post-commit
• Run script
★ If (conditions) git push to deploy repo

25. Capistrano
★More specific task for this purpose
★Better integration with ruby
★Config file is a ruby DSL

26. Talkin’ to me?

27. Use your mock server
with your apps
★Use a small router (airport express is
perfect)
★ IP parameter in the settings bundle
★ Another settings bundle for production
code.
★Consume web services as always

28. Thank
you! Images courtesy of Shutterstock