Automate your Infrastructure with Chef

Talk given at ConFoo 2013 on February 28th, 2013.

Transcript

1. Automate your Infrastructure with Chef
2. cjoudrey   @
4. c #
5. c # # # # # # # in minutes
6. # d # d c # # # # # d in minutes
7. w Manual setup takes time
8. # ruby 1.9.3 # ruby 1.9.2 != and error-prone
9. # ruby 1.9.3 # ruby 1.9.2 != Oops! and error-prone
10. What is ?! Chef
11. 1 Manage servers with ruby code
12. instead of $ ssh root@app1 Last login: Thu Feb 28 ... # apt-get install nginx ... # vim /etc/nginx/nginx.conf ... # apt-get install ruby ...
13. client server
14. # node # node # node # chef server (server1 to server3.example.com) (chef.example.com) knife ! (local machine)
15. # node # node # node # chef server (server1 to server3.example.com) (chef.example.com) knife ! (local machine)
16. # node # node # node # chef server (server1 to server3.example.com) (chef.example.com) knife ! (local machine)
17. # node # node # node # chef server chef-client (server1 to server3.example.com) knife ! (local machine)
18. 2terminology Chef
19. 2recipe Ruby file that contains Chef commands
20. 2cookbook Collection of Chef recipes
21. Getting started with Chef 2
22. git clone opscode/chef-repo https://github.com/opscode/chef-repo !
23. ! $ ls confoo ... cookbooks/ data_bags/ environments/ roles/
24. Install Chef on local machine !
25. ! gem install chef
26. # Hosted* Chef server from Opscode * free up to 5 nodes
27. #
28. #
29. Setup Knife on local machine !
30. # node # node # node # chef server (server1 to server3.example.com) (chef.example.com) knife ! (local machine)
31. ! $ ls confoo/.chef confoo-demo-validator.pem confoo-demo.pem knife.rb Copy files to REPO/.chef
32. ! $ cd confoo $ knife user list confoo-demo Test Knife
33. 8 Create your first cookbook $ cd confoo $ knife cookbook create nginx
34. 8 $ ls cookbooks/nginx ... attributes/ providers/ recipes/ resources/ templates/
35. package "nginx" cookbooks/nginx/recipes/default.rb
36. package installs using system’s package mgr
37. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx"
38. service defines an available service
39. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true end
40. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true action [:enable, :start] end
41. :enable start on server boot
42. :start start when Chef runs
43. 8 Upload cookbook $ knife cookbook upload nginx Uploading nginx [0.1.0]
44. Let’s test it on a node #
45. ! $ knife bootstrap \ server1.example.com Bootstrap a node
46. !
47. 2run list Ordered list of recipes and roles that get run on the node
48. ! $ knife node edit \ server1.example.com Edit a node
49. { "name": "server1.example.com", "run_list": [ ] }
50. { "name": "server1.example.com", "run_list": [ "recipe[nginx::default]" ] }
51. recipe[nginx::default] means default recipe of nginx cookbook
52. $ ssh server1.example.com server1:~# chef-client Run Chef on the node #
53. #
54. #
55. # Let’s configure nginx
56. copy from server to nginx cookbook templates/default/nginx.conf.erb /etc/nginx/nginx.conf !
57. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true action [:enable, :start] end template "/etc/nginx/nginx.conf" do source "nginx.conf.erb" notifies :reload, "service[nginx]" end
58. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true action [:enable, :start] end template "/etc/nginx/nginx.conf" do source "nginx.conf.erb" notifies :reload, "service[nginx]" end
59. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true action [:enable, :start] end template "/etc/nginx/nginx.conf" do source "nginx.conf.erb" notifies :reload, "service[nginx]" end
60. cookbooks/nginx/recipes/default.rb package "nginx" service "nginx" do supports :status => true, :restart => true, :reload => true action [:enable, :start] end template "/etc/nginx/nginx.conf" do source "nginx.conf.erb" notifies :reload, "service[nginx]" end
61. ! Upload the cookbook and run chef-client on node
62. #
63. 2 Chef is idempotent
64. ! What if we edit templates/default/nginx.conf.erb and run Chef
65. #
66. #
67. #
68. Let’s run Chef one more time #
69. #
70. 2Attributes
71. nginx/templates/default/nginx.conf.erb user www-data; worker_processes 2; pid /var/run/nginx.pid; ...
72. nginx/attributes/nginx.rb default['nginx']['worker_processes'] = 2
73. nginx/templates/default/nginx.conf.erb user www-data; worker_processes <%= node['nginx'] ['worker_processes'] %>; pid /var/run/nginx.pid; ...
74. # Override for a specific node
75. { "name": "server1.example.com", "run_list": [ "recipe[nginx::default]" ] }
76. { "name": "server1.example.com", "normal": { "nginx": { "worker_processes": 4 }, }, "run_list": [ "recipe[nginx::default]" ] }
77. 2Roles
78. roles/app-server.rb name 'app-server' description 'app-server stuff' run_list( 'recipe[nginx::default]' ) override_attributes( 'nginx' => { 'worker_processes' => 2 } )
79. ! $ knife role from file \ app-server.rb Upload a role
80. Apply the role on a node #
81. { "name": "server1.example.com", "run_list": [ "role[app-server]" ] }
82. #
83. { "name": "server1.example.com", "run_list": [ "role[base]", "role[app-server]" ] }
84. 2 Environments
85. environments/production.rb name 'production' cookbook_versions 'nginx' => '= 0.1.0'
86. { "name": "server1.example.com", "chef_environment": "production", "run_list": [ "recipe[nginx::default]" ] }
87. ! Searching for nodes $ knife search node \ role:app-server
88. 2
89. 8 Searching can be done in recipes too!
90. 8 Searching can be done in recipes too! OMFG!
91. backend app balance roundrobin server app1 10.10.0.1 check port 80 server app2 10.10.0.2 check port 80 server app3 10.10.0.3 check port 80
92. nodes = search( :node, 'role:app-server' ) template "/etc/haproxy.conf" do source "haproxy.conf.erb" variables :nodes => nodes end
93. backend www balance roundrobin <% @nodes.each do |n| %> server <%= n[:hostname] %> <%= n[:ipaddress] %> check port <% end %>
94. 2Goodies
100. Automation is important
101. # staging/CI # production ! development = =
102. Thanks!
103. cjoudrey   @