bad-ansible

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== Overview

Bad Ansible is a deliberately poorly constructed ansible project designed to give students a basic project to cleanup, refactor, and improve. It represents a newcomer's, aka newbie, approach to hacking together a functional playbook to deploy a three tier app.

The entry point, main.yml contains multiple good enough plays, and some redundant ones.

=== Goal of Bad Ansible

Set up an application that:

• Sets up a frontend1 haproxy server which load balances requests to http://frontend1.<GUID>.example.opentlc.com. ** Requests to frontend1 come in on port 80 ** Load balance requests to servers in the group apps, listening on port 8080
• Set up one or more tomcat servers, the group apps, to: ** Serve the included HTML content from /usr/share/tomcat/webapps/ROOT/index.html
• Install postgres on all servers in the group appdbs

Nothing else matters i.e. you can get rid of it!

=== Tips

• Make sure you have read the Goals section above and understand the desired architecture
• There are redundant plays within main.yml
• You should be able to run your solution multiple times, not just once
• You are free to restructure your solution in any way

NOTE: Any plays or tasks not related to the above are therefore redundant and can be removed.

TIP: Don't rename any of the ansible groups: frontends, apps, appdbs - later labs require these!

=== Usage

. Set up the environmental variable GUID to your GUID + [source,bash]

export GUID=abcd

. Edited your ansible.cfg depending if you are executing on bastion or remotely

• Pay attention to the value of ssh_args . Configure your chosen ssh config file
• Set the correct user
• Set the correct key(s)
• If necessary, e.g. executing from a remote control node, install the right key(s)

NOTE: You can easily test your chosen ssh config file e.g. ssh -F ssh.cfg app1 etc . Execute your main wrapping playbook [source,bash]

ansible-playbook main.yml

=== Structure

[source,bash]

. ├── README.adoc <1> ├── ansible.cfg <2> ├── cleanup.yml <3> ├── haproxy.cfg.j2 <4> ├── hosts <5> ├── index.html.app1 <6> ├── index.html.app2 <6> ├── index.html.j2 <6> ├── main.yml <7> ├── ssh-bastion.cfg <8> └── ssh-laptop.cfg <9>

. This README file . Simple ansible.cfg . Convenience playbook that removes the 3tier app - use to retest your work . A badly written jinja2 template for HAProxy - HINTS ** This should loop over the apps group ** Perhaps the Tomcat port should be a variable? . inventory file - referenced from ansible.cfg ** Note the use of a lookup in line 2, if you prefer consider: ** Hard coding it GUID=abcd or passing it in via -e GUID=abcd. . Too many index.html files? . Main entry point . ssh configuration file for working off a bastion host . ssh configuration file for working off a laptop or remote control node

=== Potential strategies

• Divide and Conquer . Break main.yml into individual plays . Discard the redundant ones . Wrap in a main.yml or similar using import_playbooks:

• Role Play . Identify the key roles e.g. common, frontends, apps, database etc . Convert the relevant plays into roles . Create wrapping playbook with multiple plays invoking roles on groups