Jeff Geerling, author of Ansible for DevOps, demonstrates basic Ansible usage on the Dramble, a cluster of six Raspberry Pi 2 computers. This presentation was delivered on July 8, 2015, at the Ansible St. Louis meetup, at Riot Games in Clayton, MO.

1. Ansible 101
Jeff Geerling
Ansible St. Louis Meetup - July 8, 2015

2. Who am I?
• Jeff Geerling (geerlingguy)
• Technical Architect, Acquia
• Owner, Midwestern Mac LLC
• Dev (mainly), Ops

3. Ansible for DevOps
• On LeanPub
• Nearly complete!
• 50% off: http://bit.ly/ansible-stl

4. My Story
• First 'real' server build: a 486 PC, RedHat Linux 6
Gateway 2000 4DX2-66v
RedHat Linux 6.x

5. Today
Midwestern Mac Server Check.in Hosted Apache Solr
Personal
= 50+ prod servers,
one very part-time sysadmin

6. • “Configuration management for humans.”
• Uses SSH
• Secure, fast, simple
• 300+ built-in modules
• Don't need configuration management to manage
your configuration management.

7. • “Configuration management for humans.”
• Uses SSH
• Secure, fast, simple
• 300+ built-in modules
• Don't need configuration management to manage
your configuration management.
___________
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And
cows!
>
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^__^
(oo)_______
(__)
)/
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8. Installation
• Python pip: sudo pip install ansible
• Mac: brew install ansible
• RHEL/CentOS/Fedora: sudo yum install ansible
• Deb/Ubuntu:
sudo apt-add-repository ppa:ansible/ansible
sudo apt-get update
sudo apt-get install ansible

9. Ansible 101
1. Inventory: Describe your infrastructure
2. Ad-Hoc commands: Run one-off tasks
3. Playbooks: "Infrastructure as code"
4. Roles: Encapsulate configuration

10. http://robmyers.org/cc-ironies/no_flash_photography_sign/
Please help me avoid the
Xenon Death Flash

11. • 6-node Raspberry Pi cluster
CPU 24 cores / 5.4 GHz
RAM 6 GB
Storage 96 GB microSD
Network 10/100 over Gig
https://github.com/geerlingguy/raspberry-pi-dramble
The #Dramble

12. Inventory
[balancer]
10.0.1.60
[webservers]
10.0.1.61
10.0.1.62
10.0.1.63
10.0.1.64
[database]
10.0.1.65
[dramble:children]
balancer
webservers
database
[dramble:vars]
ansible_ssh_user=pi
• INI-syntax (can also use YAML and dynamic sources)
• Default location: /etc/ansible/hosts (can override with -i)

13. • Check connectivity (always a good first step!)
$ ansible all -m ping
• Have fun with RGB LEDs!
$ ansible webservers -a "rgb red" -s
Ad-Hoc Commands

14. • Check connectivity (always a good first step!)
$ ansible all -m ping
• Have fun with RGB LEDs!
$ ansible webservers -a "rgb red" -s
Ad-Hoc Commands
________
<
Shiny!
>
-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐
^__^
(oo)_______
(__)
)/
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15. Demo
# Test connectivity.
ansible all -m ping
# Raspberry Pi RGB LEDs.
ansible all -a "rgb green" -s
ansible all -a "rgb blue" -s --forks=1
ansible all -a "rgb green" -s --forks=2
ansible all -a "colors 255 255 255" -s
# More useful commands.
ansible all -m setup
ansible all -a "free -m"
ansible all -m shell -a "ifconfig | grep inet" -s
ansible all -m user -a "name=pgibbons state=absent remove=yes" -s
ansible webservers -m service -a "name=nginx state=restarted" -s --forks=2
Download playbook examples

16. Playbooks
• Ad-Hoc commands don't solve the snowflake
problem
• "infrastructure as code"
• Simple YAML files
• Run with: ansible-playbook
Unique, by Pen Waggener

17. Playbooks
#!/bin/bash
# Shell script to install/configure Apache.
# Install Apache.
yum install --quiet -y httpd httpd-devel
# Copy configuration files.
cp /path/to/config/httpd.conf
/etc/httpd/conf/httpd.conf
cp /path/to/config/httpd-vhosts.conf
/etc/httpd/conf/httpd-vhosts.conf
# Start Apache.
service httpd start
# Set Apache to run on startup.
chkconfig httpd on

18. Playbooks
#!/bin/bash
# Shell script to install/configure Apache.
# Install Apache.
yum install --quiet -y httpd httpd-devel
# Copy configuration files.
cp /path/to/config/httpd.conf
/etc/httpd/conf/httpd.conf
cp /path/to/config/httpd-vhosts.conf
/etc/httpd/conf/httpd-vhosts.conf
# Start Apache.
service httpd start
# Set Apache to run on startup.
chkconfig httpd on
---
# Playbook to install/configure Apache.
hosts: all
tasks:
- name: Install Apache.
yum: name={{ item }} state=present
with_items:
- httpd
- httpd-devel
- name: Copy configuration files.
copy: "src={{ item.src }} dest={{ item.dest }}"
with_items:
- { src: "/path/to/config/httpd.conf",
dest: "/etc/httpd/conf/httpd.conf" }
- { src: "/path/to/config/httpd-vhosts.conf",
dest: "/etc/httpd/conf/httpd-vhosts.conf" }
- name: Ensure Apache is started and runs on startup.
service: name=httpd state=started enabled=yes

19. Demo
# Run just the users playbook.
ansible-playbook users.ml
# Run the users playbook again, to demonstrate idempotence.
ansible-playbook users.yml
# Run the web playbook (twice, again).
ansible-playbook web.yml
ansible-playbook web.yml
# Run the main playbook that includes users.yml and web.yml
ansible-playbook main.yml
ansible-playbook main.yml
Download playbook examples

20. Roles
• Like: Libraries, packages, config bundles
• Encapsulate configuration in smaller, reusable
chunks
• 4,000+ contributed roles on Ansible Galaxy
• To create: ansible-galaxy init [role-name]

21. Demo
Role folder structure:
rolename/
defaults/
main.yml <-- Most variables go here, so you can override if needed.
handlers/
main.yml
meta/
main.yml
tasks/
main.yml
tests/ <-- See Testing Ansible Roles with Travis CI on GitHub
vars/
main.yml <-- Special and static variables go here.
Download playbook examples

22. More Ansible
• Ansible Tower, Jenkins integration, CI
• Docker integration
• AWS, DigitalOcean, Rackspace, Softlayer, Linode, etc.
• Notifications
• Rolling updates
• Ansible Vault
• etc...

23. More Ansible
• Ansible Tower, Jenkins integration, CI
• Docker integration
• AWS, DigitalOcean, Rackspace, Softlayer, Linode, etc.
• Notifications
• Rolling updates
• Ansible Vault
• etc...
______________________________
<
Follow
@AnsiBull
on
Twitter!
>
-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐-­‐
^__^
(oo)_______
(__)
)/
||-­‐-­‐-­‐-­‐w
|
||
||

24. More Resources
• Ansible documentation
• Ansible Vagrant examples
• Ansible for DevOps
• 50% off: http://bit.ly/ansible-stl
• Raspberry Pi Dramble
• Example playbook from this presentation