EPIC: Improve our use of ansible to use best practices

[sxa]

Quite a lot of our ansible use has been "improvised" over the years. We should revisit areas where we see improvements that can be made and try and "do the right thing" in each case to become a shining example of how to use ansible!

[sxa]

• CenOS 6-7 SSL role Ansible request for CentOS6_Cent7SSL role to follow best practises #2373
• Some work in AIX PRs to make better use of roles: aixPB: first PR to start the cleanup and restructure of AIX playbooks #2453 AIXpb: version02: cleanup stage 02 #2483

[aixtools]

As long as you don't expect it all done by tomorrow - I am willing to invest time in this - building on my experience as I redo AIX playbooks - on a parallel path.

[Willsparker]

I'd love to help too! Though maybe that goes without saying..

[Haroon-Khel]

We should also define what 'best practices' are (if there does not already exists a wiki page somewhere). For starters, I like @Willsparker's encouragement of idempotency (for roles which we do not already do it) in #2373

Some others

• Clean up of downloaded tar files when necessary
• Modularity; ensure that we keep roles separated when they can

[Willsparker]

Funny you mention that, @Haroon-Khel , a wiki page does exist!

That sort of goes into the nitty-gritty of 'best practices' (i.e. playbook structure, inventory structure etc.), but the best way to put it is, the playbooks need to be idempotent, modular and easily human-readable. I recently made a small playbook that sets up Nagios-Core for #2445 , with these in things mind.

Other things, maybe more specific to Adopt, is to not use shell or command where at all possible, and when you do use them, ensure that changed_when is used ( See: #2424 and #2450 ), I do concede that, with our playbooks being so monolithic (i.e. supporting multiple platforms, on multiple architectures, some of which are EOL), best practices can be a hard thing to keep going.

[sxa]

ensure that changed_when is used ( See: #2424 and #2450 )

changed_when is also being used more in the AIX playbooks in @aixtools' PRs at https://github.com/adoptium/infrastructure/pull/2453/files and https://github.com/adoptium/infrastructure/pull/2483/files

[aixtools]

From the wiki page @Willsparker mentioned - imho: a good start for re-structuring the Unix playbooks will be using something suggested here: https://docs.ansible.com/ansible/2.8/user_guide/playbooks_best_practices.html#id24

[sxa]

Related: #1757