Can You Manage Me Now?

Humanizing Configuration Management at Scale

Tray Torrance SRE, Twitter

Introduction

Who What

Where When Why

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Problem Space

Millions of LoC Thousands of Nodes

Hundreds of Contributors Several Coding Styles

Disparate Agent Versions

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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

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Factoring the Problem

Code Hygiene (Dupe Code, Linting) Coding Best Practices

Customer Education & Assistance Software Lifecycle Management

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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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Plan of Attack: Coding Best PracticesAdopt 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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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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Plan of Attack: Upgrades

Unify Your Masters Agents Will Follow

Future-proof the Process

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On SCM MigrationsEvolution: 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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Are We There Yet?

The boss wants to know…

11Image provided by Wikipedia

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

Acknowledgements

Ramin K Jesse M Management PuppetConf

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