Let's automate stuff with Ansible

With ansible, orchestrating machines is getting easy. Defining how a host should look like in yaml, you are able to set it up with just one command. While this is certainly useful for production systems, ansible can be used to quickly set up new testing machines, development environments (e.g. inside a virtual machine) or even your localhost.

Within this talk, we'll go into the world of DevOps, seeing what it's like to control many servers without ever manually logging into them. In the beginning the ansible architecture will be explained briefly. We'll look into how a small ansible setup looks like and what can be achieved with ansible. The talk will also provide information on the difference to other configuration management tools like chef and puppet. Best practice examples will conclude the talk.

Transcript

1. Let’s automate stuff with
   Ansible
   DrupalCamp Vienna 2015
   https://www.dropbox.com/s/wmsqf8xg74bevy6/53H.jpg
   @Sgoettschkes
   

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2. It started
   with bare metal ...
   

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3. … and then
   the cloud happened
   

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4. “99 servers in the cloud, 99 servers
   Take one down, tear it apart, 98 servers in the cloud”
   Unknown
   

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6. Ansible
   

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7. Ansible
   

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8. Ansible
   

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9. Installation
   pip, brew, apt
   or
   From source (It’s just Python!)
   

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10. Inventory
    $ cat hosts
    [webservers]
    127.0.0.101 ansible_ssh_port=2222
    127.0.0.102 ansible_ssh_user=admin
    [dbservers]
    127.0.0.103 ansible_sudo=true
    

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11. Inventory
    $ cat hosts
    [webservers]
    127.0.0.101 ansible_ssh_port=2222
    127.0.0.102 ansible_ssh_user=admin
    [dbservers]
    127.0.0.103 ansible_sudo=true
    

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12. Ad-Hoc commands
    $ ansible all -m ping
    127.0.0.101 | success >> {
    "changed": false,
    "ping": "pong"
    }
    127.0.0.102 | success >> {
    "changed": false,
    "ping": "pong"
    }
    

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13. Ad-Hoc commands
    $ ansible all -m copy -a "src=/etc/hosts dest=/tmp/hosts"
    $ # or
    $ ansible all -m command -a "echo $TERM"
    

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14. Tasks
    

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15. Tasks
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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16. Modules
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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17. Tasks
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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18. Tasks
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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19. Tasks
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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20. Tasks
    $ cat tasks.yml
    ---
    - name: update apt cache
    apt: update_cache=yes
    - name: install vim
    apt: pkg=vim state=latest
    - name: install composer
    shell: curl -sS https://getcomposer.org/installer | php
    chdir=/usr/local/src creates=/usr/local/src/composer.phar
    

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21. Tasks
    $ cat tasks.yml
    ---
    - name: install packages
    apt: pkg={{ item }} state=latest
    with_items:
    - emacs
    - vim
    

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22. Tasks
    $ cat tasks.yml
    ---
    - name: install packages
    apt: pkg={{ item }} state=latest
    with_items:
    - emacs
    - vim
    when: ansible_os_family == “Debian”
    

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23. Modules
    - apt, homebrew, pacman, …
    - and pip, gem, npm, composer, …
    - copy, file, template, …
    - PostgreSQL, MySQL, MongoDB, redis, …
    - git, hg, bzr, subversion, ...
    - Monitoring, Network, Cloud, ...
    

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24. Handlers
    $ cat handlers.yml
    - name: reload nginx
    service: name=nginx state=reloaded
    - name: restart nginx
    service: name=nginx state=restarted
    

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25. Handlers
    $ cat handlers.yml
    - name: reload nginx
    service: name=nginx state=reloaded
    - name: restart nginx
    service: name=nginx state=restarted
    

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26. Handlers
    $ cat tasks.yml
    ---
    - name: install nginx
    apt: pkg=nginx state=latest
    notify: restart nginx
    

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27. Templates
    $ cat templates/nginx.conf.j2
    user {{ nginx_user }};
    worker_processes {{ nginx_worker_processes }};
    pid /var/run/nginx.pid;
    

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28. Variables
    $ cat templates/nginx.conf.j2
    user {{ nginx_user }};
    worker_processes {{ nginx_worker_processes }};
    pid /var/run/nginx.pid;
    

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29. Facts
    $ cat group_vars/webservers.yml
    nginx_user: www-data
    nginx_worker_processes: "{{ ansible_processor_cores *
    ansible_processor_count }}"
    

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30. Roles
    ● Grouping tasks
    ● Separated
    ● e.g. nginx, python, nodejs, mongodb, ...
    

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31. Putting it all together
    https://www.dropbox.com/s/en9t0dmeanbi2du/188H.jpg
    

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32. Folder structure
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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33. Inventory files
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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34. Inventory files
    $ cat environments/staging/inventory
    127.0.0.101 ansible_ssh_user=deploy ansible_sudo=true
    [webservers]
    127.0.0.101
    [dbservers]
    127.0.0.101
    

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35. Group vars
    $ cat environments/staging/group_vars/all.yml
    ---
    env: staging
    domain_www: staging.example.com
    domain_static: static.staging.example.com
    

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36. Group vars
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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37. Group vars
    $ cat group_vars/all.yml
    ---
    apt_packages:
    - acl
    - curl
    - git
    - tmux
    - vim
    

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38. site.yml
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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39. site.yml
    $ cat site.yml
    ---
    - hosts: all
    roles:
    - apt
    - iptables
    - locale
    - include: webservers.yml
    - include: dbservers.yml
    

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40. webservers.yml
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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41. webservers.yml
    $ cat webservers.yml
    ---
    - hosts: webservers
    roles:
    - nginx
    - php
    

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42. roles
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    

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43. roles
    $ ls -a .
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    $ ls roles
    apt iptables locale nginx php
    

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44. roles
    . .. dbservers.yml environments .git .gitignore group_vars
    host_vars README.md requirements.yml roles site.yml
    webservers.yml
    $ ls roles
    apt iptables locale nginx php
    $ ls roles/php/
    defaults LICENSE meta README.md tasks templates
    

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45. Roles
    $ ls roles
    apt iptables locale nginx php
    $ ls roles/php/
    defaults LICENSE meta README.md tasks templates
    $ ls roles/php/tasks
    main.yml php.yml
    

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46. Roles
    $ cat roles/php/tasks/main.yml
    ---
    - include: php.yml tags=php
    

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47. Roles
    $ cat roles/php/tasks/php.yml
    ---
    - name: install php packages
    apt: default_release={{ php_default_release }} pkg={{ item }}
    state=latest
    with_items:
    - php5-cli
    - php5-common
    

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48. Roles
    - name: configure cli php.ini
    ini_file: dest=/etc/php5/cli/php.ini option={{ item.key }}
    section={{ item.section }} value={{ item.value }}
    with_items: php_config_cli
    

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49. Roles
    $ cat roles/php/defaults/main.yml
    ---
    php_default_release: stable
    php_config_cli:
    - { section: date, key: date.timezone, value: UTC }
    - { section: PHP, key: memory_limit, value: “{{
    (ansible_memtotal_mb / 100) * 50}}M” }
    

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50. Let’s go
    $ ansible-playbook -i environment/staging/inventory site.yml
    $ ansible-playbook -i environment/staging/inventory \
    webservers.yml
    $ ansible-playbook -i environment/staging/inventory \
    -t php site.yml
    

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51. Let’s go
    TASK: [apt | install nginx]
    ok: [127.0.0.101]
    TASK: [php | install php packages]
    changed: [127.0.0.101] => (item=php5-cli,php5-common)
    TASK: [locale | copy localtime template]
    skipped: [127.0.0.101]
    

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52. There is more!
    http://publicdomainarchive.com/wp-content/uploads/2015/03/public-domain-images-free-stock-photos-autumn.jpg
    

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53. Ansible 2.0
    “Ansible 2 is coming, and it’s going to be awesome!”
    James Cammarata (Director of Ansible Core Engineering)
    

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54. IT Automation
    https://www.dropbox.com/s/x8b4iqm82di9abr/186H.jpg
    

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55. https://www.dropbox.com/s/6z5aiwa8l09g2pa/86H.jpg
    

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