lessons learned in the osuosl puppet migration
Post on 18-Oct-2014
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DESCRIPTION
The OSU Open Source Lab has used CFengine 2 over the past ten years and the code has exploded towards over 14,000 lines of code. We had set out to migrate to Puppet over four years ago and still haven't completed the process. We have made several mistakes over that time and this session will discuss some of the do's and don'ts of what we learned along the way. We are finally down a path where we can make the transition and want to share our experiences. This session will also be helpful for those in the middle of a major puppet upgrade. Lance Albertson Director, OSU Open Soruce Lab Lance Albertson is the Director for the Oregon State University Open Source Lab (OSUOSL) and has been involved with the Gentoo Linux project as a developer and package maintainer since 2003. Since joining the OSUOSL in 2007, Lance has managed all of the hosting activities that the OSL provides for nearly 160 high-profile open source projects. He was recently promoted to Director in early 2013 after being the Lead Systems Administration and Architect since 2007. In his free time he helps organize Beaver BarCamp and plays trumpet in a local jazz group The Infallible Collective. He holds a B.A. in Agriculture Technology Management from Kansas State University, where he minored in Agronomy and Computer Science.TRANSCRIPT
Session Summary
● OSL team environment overview● Brief OSL systems architecture history ● CFEngine environment & stats● Initial Puppet environments● Git repo all the things!● Modules strategy● Deployment/migration strategy● Future Plans
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
OSL Team Environment
● 2 FTE Sysadmins, 1 FTE developer● 6-10 student sysadmins● 4-6 student devs● Student productivity / turnover● Multiple on-going projects● Incoming tickets keeps us busy● Domain knowledge is mostly on me*
* I'm bad at documentation
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
OSL Team Environment
Systems weekly team meeting
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
OSL Systems History● Started out on Debian ('03-'05)● Switched to Gentoo Hardened ('05-'12)○ Gentoo devs on staff (mostly me)
○ Wanted the grsec/PaX features
● Started deploying CentOS 5 ('08+)● All new deployments CentOS 6 ('12+)○ EOL schedule worked best for us
● CFEngine 2 for config management● Some mixed CFEngine/puppet env.
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
CFengine Environment
● Manages all package installs & upgrades● 180 "Services"● 174 Package classes● 113 cf. files● 19,500 lines of raw cf files● 14,700 lines actual code● 1490 lines in cf.classes alone● 24,300 commits (9,100 are mine alone)
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
CFengine Environment
● "Do all the things in cfengine"
● A lot of hacked logic because its CF 2
● Not very dynamic for our needs
● No way to delegate access to projects
● Upgrade path to CF 3 would be a nightmare
● Works very well for our Gentoo hosts
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Reason for choosing Puppet
● Liked its goals and approach overall
● Proximity to Puppet Labs (PDX)
● Lots of sharable modules and code
● Excellent community
● Very sysadmin focused
● Lots of progress in its feature set
○ Razor, Puppet Enterprise, Foreman, etc
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Puppet Migration Strategy
● Avoid mixed cfengine / puppet environments at all cost
○ Either all cfengine or all puppet
● Convert all CentOS hosts first
○ Easy transition
● Rebuild, Retire, rethink Architecture
○ Same basic architecture since 2005
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
The Beginnings
● Planning in early 2010● Summer of 2010 initial implementation● Student project● Used code from example42● Single git repo (#1) for everything● Gentoo Puppet issues○ No concept of use flags, keywords, etc
○ Package dependencies are hell
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Git repo all the things! - 2010● Fall 2010 - Git repo #2 created ● Split into repos based on projects
○ Try to solve the delegation problem
○ Manifests were done in an ugly way
○ Didn't use submodules but a simple script to keep things in sync - i.e. non-standard
● Repo is in production still today○ Drupal Project has their own module repo
○ They use it to manage their services primarily
○ We run CFengine along-side puppet on Drupal Project machines - YUCK!
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Git repo all the things! - 2011● Summer 2011 Repo #3 created● 2-3 students started it again● Partnered with PSU CAT team● Repo for every module, and submodule
everything
● Nightmare management of the super-repo● Very confusing to new students● Deployed it on all the student workstations to
test
○ Now its instance #2 that was running in production at the time
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Git repo all the things! - 2011
● Summer 2011● Added basic puppet syntax checking commit
hook
● Implemented puppet-sync○ https://github.com/pdxcat/puppet-sync
○ A script to synchronize you manifests from a GITrepository to your Puppet master.
● This helped but the submodules produced so much rage face
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Git repo all the things! - 2012
● Summer 2012○ I take a crack at fixing the repo mess
● Repo #4 is created with a slightly saner approach
● Still using submodules, but much less● Refactored a bunch of code● Did take a look at mr for repo management● Never went into production, kind of forgotten
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
“puppet-simple” repo - 2012
● Fall 2012 - "Lets get this right for real"● Very simplified multi-repo layout (K.I.S.S.)● Single repo● Directory layout:
○ dist/ - internal modules
○ libs/modules - public or internal->public modules
○ site/ - site specific modules
■ site/os - OS specific module
■ site/role - Role specific module
● Submodules for libs/*
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Repo Recap
● #1 Single git repo - deprecated
● #2 Multi-repos w/o submodules - prod (Drupal)
● #3 Multi-repos w/ submodules - deprecated
● #4 Multi-repos w/ submodules (Lance refactor)
○ never used
● #5 puppet-simple - prod (workstations)
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Lessons learned from the repos
● K.I.S.S. from the start● Submodules produces a lot of rage face● Pick something and stick with it the best
you can
● Flexibility is nice, but don't need it in the beginning
● Try to use community modules when possible
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Chef Experiment - 2013
● Wait, I thought this was a Puppet migration talk?● Decided to take another look at Chef● Testing on a small set of new machine
environments
● Has its own set of issues and problems○ Fixed some initial workflow problems we had with
puppet
● Jury is still out● “Yay” for three config management envs! </sarcasm>
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Current status of migration
● Workstations on new "simple" repo● Building base modules (80% finished)○ Importing some from the other repos, refactoring,
cleaning up
○ Using community modules (mysql, concat, etc)
● Importing OSL site specific magic
○ Converting CFengine-isms into Puppet
○ Try and undo really hacked up code and processes
● Testing and more testing
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Testing Environment● Vagrant and more vagrant○ Build standard cfengine-ized basebox
○ Run new modules to see changes
● Future Plans
○ RSpec testing on modules
○ Jenkins CI environment of some kind
● Projects' access
○ Give them an environment to test major changes
● Needs a lot of work
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Current Migration Strategy● Finish base puppet modules○ Build other modules as needed
● Deploy application service management○ Services not currently managed by CFengine
○ Will run in parallel with CFengine
● Convert all current CentOS 5/6 hosts one-by-one
● Gentoo -> CentOS Migration
○ Rebuilt as CentOS 6 under puppet
○ Retired, re-architected, etc
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Future Plans● Publish OSL modules● Delegation to projects○ Allow projects to check out their puppet config
○ Integrated testing, merging, etc
○ Less work on our staff long term
● Use other tools
○ Deploy Foreman (or something similar like PE)
○ Try out Puppet Enterprise
○ Look into PuppetDB, MCollective, Hiera, etc
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Conclusion Takeaways● Dedicate someone on the conversion○ Maintain consistency, less context switching
● Use K.I.S.S. principle as much as possible● Target specific hosts as examples for
conversion
○ Do test deploys with vagrant
● Use "brick and mortar" philosophy○ Try and keep site specific code out of the
modules the best you can
Lessons Learned in the OSUOSL Puppet MigrationLance Albertson | [email protected] | @ramereth
Questions?Lance Albertson
[email protected]@ramereth
http://osuosl.orghttp://lancealbertson.com
Follow OSUOSL@osuosl | fb.com/OSUOSL
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Creative Commons Attribution-Share Alike 3.0 United States License.Copyright 2013