Migrating from another configuration management system

Learn at a high level what it takes to move your existing configuration management to use Ansible. Shows how to get your feet wet, plan your migration, and execute the rewrite.

Transcript

1. Migrating from another configuration management system Robby Colvin @geetarista
2. $ whoami
3. About Me • Work @ Kiip • Software Engineer • Operations Engineer • Engineer
4. $ cat /etc/passwd | grep audience
5. Why choose Ansible?
6. Why choose Ansible? • Application Deployment • Cloud-aware orchestration • Ad-hoc tasks • Low barrier to entry stack-wise • Simple for developers to grasp • Python + Boto • No central server required • Flexibility
7. Is it right for you?
8. Is it right for you? • Is it cost-effective? • Does it fit your culture? • Does it align with your goals? • Can you abandon your current tooling? • Does it improve productivity?
9. Ansible 101
10. Ansible 101 • YAML • Jinja2 • Hosts • Roles • Playbooks • CLI • Modules
11. Modules • Builtin • EC2, DigitalOcean, Rackspace, Linode, et. al. • Commands • Databases • Files/Templates • Packages • Etc.
12. Migration Plan
13. Migration Plan 1. Get your feet wet 2. Plan/organize 3. Execute
14. Get Your Feet Wet
15. Get Your Feet Wet • Several options to start with Ansible
16. Get Your Feet Wet • Several options to start with Ansible • Risk free™
17. Get Your Feet Wet • Several options to start with Ansible • Risk free™ • Pick a simple role
18. Get Your Feet Wet • Several options to start with Ansible • Risk free™ • Pick a simple role • Take baby steps
19. Get Your Feet Wet • Several options to start with Ansible • Risk free™ • Pick a simple role • Take baby steps • Simple Module(s)
20. Get Your Feet Wet • Several options to start with Ansible • Risk free™ • Pick a simple role • Take baby steps • Simple Module(s) • Build on what you learn
21. Install Ansible • pip install ansible • Others: apt, yum, source
22. Configure # ansible.cfg [defaults] hostfile = production.ini private_key_file = production.pem remote_user = ubuntu sudo = True [ssh_connection] scp_if_ssh = True
23. Existing Boxes
24. Existing Boxes • CLI • --check --diff • Push from your machine • Run simple modules: ping, setup, etc. • Move on to other modules
25. Vagrant
26. Vagrant • Run from your machine to Vagrant host • Use Ansible provisioner • Go crazy • Simulate multiple hosts, clusters, etc.
27. Vagrant Ansible provisioner Vagrant.configure("2") do |config| config.vm.box = "precise64" config.vm.provision "ansible" do |ansible| ansible.playbook = "vagrant.yml" end end
28. Ansible Vagrant host Vagrant.configure("2") do |config| config.vm.box = "precise64" config.vm.network :private_network, ip: "192.168.33.10" end
29. Ansible Vagrant host # vagrant.ini 192.168.33.10 \ ansible_ssh_user = vagrant \ ansible_ssh_private_key_file = \ ~/.vagrant.d/insecure_private_key
30. Moving Forward
31. Plan
32. Take stock • Identify existing cruft • Get to know Ansible modules (don't re-invent the wheel) • Identify custom modules to be written • Integrate with infrastructure • Get to know the documentation • Learn how to use the CLI • Learn how to write Jinja2 templates
33. Organize • Host inventory
34. Host Inventory • Write inventory by hand • Use ec2.py • Write your own inventory script
35. Hosts # hosts.ini [production] 10.1.100.1 10.1.100.2 [staging] 10.2.100.1
36. Organize • Host inventory • Roles
37. Roles roles/ nginx/ files/ handlers/ library/ tasks/ templates/ vars/
38. Organize • Host inventory • Roles • Playbooks
39. Playbooks • Top-level • Include other playbooks • Node definitions
40. Playbooks --- - hosts: web roles: - common - nginx - postgresql
41. Organize • Host inventory • Roles • Playbooks • Choose a mode
42. Choose a Mode • Push • Pull • Manager (API)
43. Start the rewrite
44. Start the rewrite • Baby steps: one role at a time
45. Start the rewrite • Baby steps: one role at a time • Use --check --diff
46. Start the rewrite • Baby steps: one role at a time • Use --check --diff • Test against staging or box outside LB
47. Start the rewrite • Baby steps: one role at a time • Use --check --diff • Test against staging or box outside LB • Vagrant
48. Start the rewrite • Baby steps: one role at a time • Use --check --diff • Test against staging or box outside LB • Vagrant • Write new roles/playbooks in ansible
49. Start the rewrite • Baby steps: one role at a time • Use --check --diff • Test against staging or box outside LB • Vagrant • Write new roles/playbooks in ansible • Get everyone involved
50. Start the rewrite • Baby steps: one role at a time • Use --check --diff • Test against staging or box outside LB • Vagrant • Write new roles/playbooks in ansible • Get everyone involved • Stay up to date with documentation
51. Last Steps
52. NONE! • If done properly, you should be good to go • Just iterate and continue forward • Move on to advanced topics
53. Questions
54. Thanks! @geetarista