1. Ansible for Easy Provisioning and Application Deployment
Neal Stephenson and Diego Figueroa, UIT

2. Why Use It Simple automation tool Low requirements:
Machine with ssh server
Account that can sudo (or root)
Can crystalize knowledge
Deploy applications to your environments
only need sudo if you are going to do things that cannot be done by user that you logged in as
harden ssh example

3. Simple Example Run a command on your inventory of hosts:
ansible all -m shell -a ‘echo hi from $(hostname)’
Run a sophisticated module on your mysql servers:
ansible mysql -m mysql_user -a user=oucc -a password=123456
The word after the ansible command is the host group to use which we will see on the next slide

4. Inventory List of your hosts Grouped into sets
These groups then used to set variables and are used to determine machine roles
[managed]
html1
html2
mysql1
[html]
I tend to use a lot of groups
also special groups like :children, :vars - the latter I would avoid use group vars

5. YAML Syntax YAML is a clean syntax to write most data structures in.
variable: value
list:
item 1
item 2
hash:
key1: value1
key2: value2
even do array of hashes or hashes of arrays of hashes…
yaml is not unique to ansible

6. Group Vars
These are variables that are set due to host being in group in hosts.
There is a default all.yml group.
html.yml
---
users:
- name: us1
uid: 20001
- name: us2
uid: 20002
web_home: /webs
web_group: web
nfs_hosts:
also use to differentiate environments DEV, QA, PROD
typically, I have, groups for services and overlapping groups for environments

7. Roles
Roles are groups of tasks, files, handlers that can be used to setup a “service”
e.g. mysql role would have all the commands to install mysql, configure the database, setup root user…
I normally tie roles to groups
demo roles directory and inside a roles directory

8. Plays Plays are collections of roles and commands to do major goals.
---
# comprehensive setup
- name: settings for all hosts
hosts: all
roles:
- base
tags: base
- name: settings for managed hosts
hosts: managed
sudo: true
- managed
tags: managed
Commonly setup entire cluster of machines
Ideally they should be repeatable

9. Demo Simple OUCC Application Deploy on UAT, QA & Production
Quick Redeploy
What does this entail for Change Management?

10. Demo Files (1) django-uat.yml: inventory: --- - hosts: appserver-uat
any_errors_fatal: true
vars_files:
- "group_vars/common"
- "group_vars/{{app}}"
roles:
- user
- mysql
- git
- env
- django
- permissions
- apache
inventory:
[local]
localhost
[appserver-uat]
app05uat.uit.yorku.ca
[appserver-qa]
app05qa.uit.yorku.ca
...

11. Demo Files (2) common: oucc2016-pyork:
app_domain: "{{ my_domain | default(False) }}"
ssh_priv_key: ~/.ssh/id_rsa
oucc2016-pyork:
app_user: oucc2016
app_name: oucc2016
app_description: OUCC 2016 Ansible Demo (PYork)
app_acl: valid-user
install_root: oucc2016-pyork
initial: "{{ run_fixtures | default(False) }}"
pyork: "{{ setup_pyork | default(True) }}"
mysql: "{{ uses_mysql | default(False) }}"
...

12. Demo Files (3) roles/user/tasks/main.yml: ---
- name: Create the group for the app
group: name="{{app_user}}" gid="{{uid}}"
become: yes
register: group
- name: Create the user under which we will run the app
user: name="{{app_user}}" password=! uid="{{uid}}" group="{{app_user}}" groups=ccsdev shell=/bin/bash home="/home/{{app_user}}" comment="{{app_description}}"
when: group|success
register: user
- name: Register user SSH key
authorized_key: user="{{app_user}}" key="{{lookup('file', '~/.ssh/id_rsa.pub')}}"
become_user: root
when: user|success

13. Demo Files (4) roles/apache/templates/django.conf:
<VirtualHost *:80>
ServerName {{app_domain}}
DocumentRoot /home/{{app_user}}/{{install_root}}
ErrorLog /var/log/apache2/{{app_user}}-error.log
LogLevel warn
CustomLog /var/log/apache2/{{app_user}}-access.log combined
RedirectMatch (.*)
</VirtualHost>
<VirtualHost *:443>
...

14. Install Demo
Large play that installs a complete virtual machine environment with two apache servers, a mysql server, a tomcat server, an NFS server and a graphite server. Also installs collectd and monit on every machine.

15. Questions?

16. Thank you! Neal Stephenson neal@yorku.ca Diego Figueroa