Here are the slides from Tray Torrance's PuppetConf 2016 presentation called Can You Manage Me Now? Humanizing Configuration Management at Scale. Watch the videos at https://www.youtube.com/playlist?list=PLV86BgbREluVjwwt-9UL8u2Uy8xnzpIqa

1. Can You Manage Me Now?
Humanizing Configuration
Management at Scale
Tray Torrance
SRE, Twitter

2. Introduction
Who
What
Where
When
Why
2

3. Problem Space
Millions of LoC
Thousands of Nodes
Hundreds of Contributors
Several Coding Styles
Disparate Agent Versions
3

4. Problem Space
• Actively Hostile Codebase
• What even are types?
if enc_query(‘something’, ‘false’) == ‘true’ { … }
if enc_query(‘something’, ‘false’) != ‘false’ { … }
if enc_query(‘something’, undef ) == undef { … } # impossible
ThreadCount <%= @workers.to_i %>
“I ran Puppet, and it painted me a Picasso [with errors]”
“Sharp and Pointy by Design”
Hard to reason about by accident
4

5. Factoring the Problem
Code Hygiene (Dupe Code, Linting)
Coding Best Practices
Customer Education & Assistance
Software Lifecycle Management
5

6. Plan of Attack: Code Hygiene
Identify Duplicate Code
Refactor Common Code to Modules
Scope Linter Violations
Increase Linter Compliance
Enable Linting in SCM Hooks
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7. Plan of Attack: Coding Best Practices
Adopt Role/Profile
Make Amends with the AutoLoader
Eradicate Multi-Resource Stanzas
$ grep -ri ‘foo’ puppet/modules
puppet/modules/role/manifests/bar.pp:22 include ::foo
puppet/modules/role/manifests/baz.pp:36 include ::foo
puppet/modules/role/manifests/qux.pp:44 ’foo’:
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8. Plan of Attack: Customer Education
Be the Code You Want to See in Your Repo
Mingle With the People
Teach Them to Fish
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9. Plan of Attack: Upgrades
Unify Your Masters
Agents Will Follow
Future-proof the Process
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10. On SCM Migrations
Evolution: Good
• Better Tooling
• Better Branching
Revolution: Bad
• “I’ve only ever used $otherSCM, so we should, too!”
• “If it’s good enough for the Linux kernel, it’s good
enough for me!”
• “Isn’t $currentSCM really really old?”
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11. Are We There Yet?
The boss wants to know…
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Image provided by Wikipedia

12. You Are NEVER There
Those who don’t learn from the past,
Are doomed to refactor it.
Over and over and over.
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Image provided by @imwithstoopid13 — deviantart

13. Acknowledgements
Ramin K
Jesse M
Management
PuppetConf
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