Expert Talk - 9 June 2017. Pune. Immutable infrastructure with Terraform

1. Immutable
Infrastructure with
Terraform
- Prashant Kalkar & Rahul Baphana
(Expert Talk - Pune - 9 June 2017)

2. 1.
DevOps Journey

3. Limited hardware, manually managed.
On Premise Hardware

4. » Limited hardware
» Configured generally once.
» Long running.
» Servers might not look identical.
» Change propagation requires changes in all the
server instances.
» Manageable with small no of servers.
On-Prem Hardware

5. » Client Server Architecture
» Easy to propagate
configuration changes.
» Instances mostly look
identical.
» Long running server.
» Can face issues of
Configuration drift.
Configuration Management Tools

6. 1.1
Rise of Clouds

7. » Elastic
» Disposable resources.
» On-demand
» Cost effective
Cloud properties

8. » Infrastructure Provisioning.
» Configuration of new
instances.
» Delays at server runtime for
server configuration.
» Possible failure of server
configuration at runtime.
Challenges in the Cloud

9. 2
Immutable Infrastructure

10. Machine Image /
Container
Ubuntu
Chef / Puppet
client
Manages
EC2 Instances
Configuration
Management Tool
App artifact
Java
Tomcat
Logstash client
Mutable Infrastructure

11. Machine Image /
Container
Ubuntu
Server Templating Tools App artifact
Java
Tomcat
Logstash client
EC2 Instances
Chef / Puppet
client
Manages
EC2 Instances
Configuration
Management Tool
App artifact
Java
Tomcat
Logstash client
Immutable Infrastructure

12. 3
Terraform

13. » Declarative style for infrastructure as code
» Supports multiple cloud providers
» Easier to adopt for new teams
» Open source
» Under active development
Why Terraform

14. 3.1
Terraform Demo

15. » Sample web app on EC2 instance
» AMI for spring-boot-app
Demo

16. » No client-server
» Terraform tfstate (show command)
» Resource dependency & Parallel Execution
» Terraform failures
» Incremental changes
» Non-managed infrastructure is invisible to Terraform
How Terraform is working?

17. » Remote state
» State locking
» Practices :
⋄ Use centralise server to apply Infrastructure changes
⋄ Always apply Terraform on a pushed code base
⋄ Branches or no branches?
Using Terraform in a team

18. » Rolling deployments
» Output variables
Demo

19. Launch
Config-1
Rolling
Deployment

20. Launch
Config-1
Launch
Config-2
Rolling
Deployment

21. Launch
Config-2
Rolling
Deployment

22. » Supporting multiple environments
⋄ Per environment tfstate (recommended)
⋄ Keep state as minimum as possible
⋄ Read only state
⋄ Use profiles
Demo

23. » Using modules to dry out Terraform code
⋄ Relative modules
⋄ Terraform Variables
⋄ Modules with versions
Demo

24. THANKS!
Any questions?