Module 4 of Chef for Beginners Workshop at Optum-Chef DevOps Transformation Day in Minneapolis on April 21st 2016

1. chef-client
Applying Recipes from Cookbooks
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2. After completing this module, you should be able to use
chef-client to:
Locally apply a cookbook's recipe with chef-client.
Locally apply multiple cookbooks' recipes with chef-
client.
Include a recipe from within another recipe.
Objectives
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3. chef-apply is a great tool for applying resources (-e)
and for individual recipes but it doesn't know how to
apply a cookbook.
chef-apply
https://docs.chef.io/ctl_chef_apply.html
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4. chef-client is an agent that runs locally on every node
that is under management by Chef.
When a chef-client is run, it will perform all of the
steps that are required to bring the node into the
expected state.
chef-client
https://docs.chef.io/chef_client.html
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5. chef-client's default mode attempts to contact a Chef
Server and ask it for the recipes to run for the given
node.
We are overriding that behavior to have it work in a
local mode.
--local-mode
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6. In local mode, we need to provide a list of recipes to
apply to the system. This is called a run list. A run list
is an ordered collection of recipes to execute.
Each recipe in the run list must be addressed with the
format recipe[cookbook-name::recipe-name].
-r "recipe[cookbook-name::recipe-name]"
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7. When you are referencing the default recipe within a
cookbook you may optionally specify only the name of
the cookbook.
chef-client understands that you mean to apply the
default recipe from within that cookbook.
-r "recipe[cookbook-name(::default)]"
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8. Example Usage
Using chef-client to locally apply the setup recipe from the workstation
cookbook.
$sudochef-client--local-mode–r"recipe[workstation::setup]"
Applyingthefollowingrecipeslocally:
The'setup'recipefromthe'workstation'cookbook
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9. Example Usage
Using chef-client to locally apply the server recipe from the apache cookbook.
$sudochef-client--local-mode-r"recipe[apache::server]"
Applyingthefollowingrecipeslocally:
The'server'recipefromthe'apache'cookbook
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10. Example Usage
Using chef-client to locally apply multiple recipes from multiple cookbooks.
$sudochef-client--local-mode
-r"recipe[workstation::setup],recipe[apache::server]"
Applyingthefollowingrecipeslocally:
*The'setup'recipefromthe'workstation'cookbook
*The'server'recipefromthe'apache'cookbook
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11. Group Exercise: Return Home First
$cd~
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12. Group Exercise: Apply the apache::server Recipe Locally
$sudochef-client--local-mode-r"recipe[apache::server]"
[2015-09-15T14:52:45+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
[2015-09-15T14:52:45+00:00]WARN:Nocookbooksdirectoryfoundatorabovecurrentdirectory. Assuming/home/chef.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["apache::server"]
================================================================================
ErrorResolvingCookbooksforRunList:
================================================================================
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13. Group Exercise: Apply the apache::server Recipe Locally
$sudochef-client--local-mode-r"recipe[apache::server]"
[2015-09-15T14:52:45+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
[2015-09-15T14:52:45+00:00]WARN:Nocookbooksdirectoryfoundatorabovecurrentdirectory. Assuming/home/chef.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["apache::server"]
================================================================================
ErrorResolvingCookbooksforRunList:
================================================================================
FAIL
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14. Group Exercise: Create a cookbooks directory
chef-client requires the cookbooks to be in a cookbooks directory located
in the user's home directory.
$cd~
$mkdircookbooks
$mvworkstationcookbooks
$mvapachecookbooks
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15. Group Exercise: Apply the apache::server Recipe Locally
$sudochef-client--local-mode-r"recipe[apache::server]"
[2015-09-15T14:54:45+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["apache::server"]
SynchronizingCookbooks:
-apache
CompilingCookbooks...
Converging4resources
Recipe:apache::server
*yum_package[httpd]actioninstall(uptodate)
*file[/var/www/html/index.html]actioncreate(uptodate)
*service[httpd]actionenable(uptodate)
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16. Group Exercise: Apply the workstation::setup Recipe Locally
$sudochef-client--local-mode-r"recipe[workstation::setup]"
[2015-09-15T15:15:26+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["workstation::setup"]
SynchronizingCookbooks:
-workstation
CompilingCookbooks...
Converging6resources
Recipe:workstation::setup
*yum_package[nano]actioninstall(uptodate)
*yum_package[vim]actioninstall(uptodate)
*yum_package[emacs]actioninstall(uptodate)
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17. Group Exercise: Apply Both Recipes Locally
$sudochef-client--local-mode
-r"recipe[apache::server],recipe[workstation::setup]"
[2015-09-15T15:17:27+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["apache::server","workstation::setup"]
SynchronizingCookbooks:
-apache
-workstation
CompilingCookbooks...
Runninghandlers:
[2015-09-15T15:17:30+00:00]ERROR:Runningexceptionhandlers
Runninghandlerscomplete
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18. A recipe can include one (or more) recipes located in
cookbooks by using the include_recipemethod.
When a recipe is included, the resources found in that
recipe will be inserted (in the same exact order) at the
point where the include_recipekeyword is located.
include_recipe
https://docs.chef.io/recipes.html#include-recipes
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19. Example Usage: Including a Recipe
Include the setup recipe from the workstation cookbook in this recipe.
include_recipe'workstation::setup'
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20. Example Usage: Including a recipe
Include the server recipe from the apache cookbook in this recipe.
include_recipe'apache::server'
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21. Group Exercise: The default recipe includes the setup recipe
~/cookbooks/workstation/recipes/default.rb
#
#CookbookName::workstation
#Recipe::default
#
#Copyright(c)2015TheAuthors,AllRightsReserved.
include_recipe'workstation::setup'
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22. Group Exercise: Apply the cookbook's default recipe
$sudochef-client--local-mode-r"recipe[workstation]"
WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["workstation"]
SynchronizingCookbooks:
-workstation
CompilingCookbooks...
Converging0resources
Runninghandlers:
Runninghandlerscomplete
ChefClientfinished,0/0resourcesupdatedin3.300489827seconds
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23. Group Exercise: Commit Your Work
$cdworkstation
$gitadd.
$gitcommit-m"Defaultrecipeincludesthesetuprecipe"
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24. Update the apache cookbook's default recipe to:
Include the server recipe from the
apache cookbook
Run chef-client and locally apply the run list:
recipe[apache]
Commit the changes with version control
Lab: Update the apache Cookbook
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25. Lab: The default recipe includes the apache recipe
~/cookbooks/apache/recipes/default.rb
#
#CookbookName::apache
#Recipe::default
#
#Copyright(c)2015TheAuthors,AllRightsReserved.
include_recipe'apache::server'
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26. Lab: Applying the apache default recipe
$sudochef-client--local-mode-r"recipe[apache]"
[2015-09-15T15:23:18+00:00]WARN:Noconfigfilefoundorspecifiedoncommandline,usingcommandlineoptions.
StartingChefClient,version12.3.0
resolvingcookbooksforrunlist:["apache"]
SynchronizingCookbooks:
-apache
CompilingCookbooks...
Converging0resources
Runninghandlers:
Runninghandlerscomplete
ChefClientfinished,0/0resourcesupdatedin3.310768509seconds
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27. Lab: Commit Your Work
$cdapache
$gitadd.
$gitcommit-m"Defaultrecipeincludestheserverrecipe"
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28. Why would you want to apply more than one recipe at
a time?
Discussion
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29. Why would you want to apply more than one recipe at
a time?
What are the benefits and drawbacks of using
include_recipewithin a recipe?
Discussion
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30. Why would you want to apply more than one recipe at
a time?
What are the benefits and drawbacks of using
include_recipewithin a recipe?
Do default values make it easier or harder to learn?
Discussion
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31. Q&A
What questions can we help you answer?
chef-client
local mode
run list
include_recipe
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32. On to Module 5
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