Ansible Talk @ Infra Coders

Here are the notes that I used in my talk at Infrastructure Coders. Each section was also put on the screen as a ‘slide’. The configuration that I used in the demo is available at GitHub. A full video of the meetup is available on the Infrastructure Coders Youtube Channel, my talk starts at 25:05.

Ansible
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0. There is nothing in the hat
  - Start a RHEL install
    - Cmd line: console=ttyS0 ks=http://admin01/ns3.cfg
    - If you want to follow the demos grab the ansible config from my github
    - You will need to substitute hostnames in the ansible hosts file
    - You should copy the firewall config from ns2 (remove port 647 if paranoid)

1. The problem
  - Ansible is the combination of several functions
  - There was a plan to build config management on func
  - However func is a pain to setup
  - Puppet and Chef have a steep learning curve
  - Ansible was also built to simplfy complexrelease procedures
  - You need to know ruby to extend Puppet/Chef

2. Ansible
  - Designed so you can figure out how to use it in 15 minutes
  - Designed to be easy to setup
  - Doesn't require much to be installed on the managed host
  - Designed to do config management/deployment/ad hoc
  - Other people do security better, just use SSH
  - You can extend ansible in any language that can output JSON

3. Simple Ansible Demo
  - Ansible hosts file
  - Ansible can be run directly on the command line
    - Run cat /etc/redhat-release
    - Get info using the setup module
  - It can prompt for auth, or use key based auth
    - On the new machine show it prompting
    - Run the rhelsetup script on the new machine
    - Install vim-enhanced

4. Playbooks
  - This is the method of scripting Ansible
  - Done in YAML
  - Executed in order *gee thanks puppet*
  - Designed to be as easy as possible

5. Example playbook
  - Playbook for the name servers
    - https://github.com/smarthall/tildaslash.com/blob/master/playbooks/zones.play
    - Can have multiple plays in a book
    - Can serialise if you dont want all to be down at once
  - Template config for the name servers
    - https://github.com/smarthall/tildaslash.com/blob/master/playbooks/zones/named.conf.j2
  - Firewall install script
    - https://github.com/smarthall/tildaslash.com/blob/master/playbooks/firewall.play

6. My thoughts
  - Config management has been around a while, its going from art to science
  - Ansible covers more ground than puppet and chef do
  - Ansible doesn't compromise on simplicity to do that
  - I don't have to focus on the nodes, I can focus on services
  - There is something missing
    - Disk config is done in kickstarts
    - Network config can't be done by Ansible
    - Need to find a way to cover both with one

The playlist of all the videos is available at Youtube.