Principles, Patterns, and Practices for Effective Infrastructure as Code Deliver Infrastructure and Software running on it Rapidly and Reliably at Scale Adarsh Sha h Engineering Leader, Coach, Hands-on Architec t Independent Consultan t @shahadarsh 
 https://shahadarsh.com Deck: https://bit.ly/IaC-FOSDEM

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Infrastructure as Code Infrastructure as Code (IaC) is an approach that takes proven coding techniques used by software systems and extends it to infrastructure. It is one of the key DevOps practices that enable teams to deliver infrastructure, and the software running on it, rapidly and reliably, at scale.

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Key Principles

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Idempotency Idempotency means no matter how many times you run your IaC and, what your starting state is, you will end up with the same end state. This simpli f i es the provisioning of Infrastructure and reduces the chances of inconsistent results.

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Non-Idempotent Provision VM VM VM { } IaC 3 VMs End State
 Expected = 3 Actual = 6 Idempotent End State
 Expected = 3 Actual = 3 Reapply VM VM VM Provision VM VM VM Reapply No change { } IaC 3 VMs

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Immutability Immutable infrastructure means instead of changing an existing infrastructure you replace it with new. By provisioning new infrastructure every time, you are making sure it is reproducible and doesn’t allow for con f i guration drift over time.

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Provision v1 v1 v1 User Mutable Infrastructure { } IaC Apply changes v2 v2 v2 Change { } IaC v1 v1 v1 Provision User Provision v2 v2 v2 User Immutable Infrastructure { } IaC Change { } IaC Deploys v2 to same Infrastructure Provisions new Infrastructure with v2

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Patterns and Practices

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Source Control Everything in Source Control Accessible t o Everyone

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Modularize and Version Maintenance Readability Ownership

Application Owner: 
 Application Team App Deploy Platform Owner: 
 Platform Engg. Team Network Owner: 
 Networking Team Account Owner: 
 Security/Platform Engg. Team Bootstrap Owner: 
 Platform Engg. Team Common Storage Account Settings VPC/ Subnet Common Network Database Cluster EKS App Database App Storage All Application Infrastructure gets provisioned along with Application Deployment in this Layer Application Platform Layer for provisioning anything needed to run applications on All Networking including connections to other networks gets provisioned in this Layer All AWS Account Level resources get provisioned in this Layer Any Bootstrapping needed for running above Layers like Service Account with permissions to run IaC & IaC State Bucket Infrastructure Layers Example State S3 Bucket Service Account

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Documentation Easily available Closer to the code Keep it updated

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Static Analysis terraform validate, TFLint, puppet parser validate Cost and Duration Unit Tests Bats, chefspec Integration Tests InSpec, goss Smoke Tests w/ dummy app Selenium, JMeter Brittleness and Maintenance IaC Testing

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Security and Compliance Identity & Access Management Secrets Management Security Scanning Compliance

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Automate Execution from a Shared Environment

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM VM VM VM Static Analysis Unit Tests Continuous Integration Compliance Integration Tests Security VM VM VM Testing & Validation Ephemeral Environment Provision Smoke Tests Smoke Tests Note: This example is for Platform Layer but similar pipeline should be added for other layers (account, network & application) IaC Pipeline

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM GitOps GitOps = IaC + (Work f l ow + Control Loop)

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Create Pull Request , Plan & Tests Terraform Apply VM VM VM Terraform Plan & Tests Approve & 
 Merge PR Control Loop Verify Desired & Actual State Sync (if different) Provision GitOps

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Talk based On Article on my website: http://bit.ly/IaC-PP Contributed to the new O’Reilly book

https://shahadarsh.com @shahadarsh Deck: https://bit.ly/IaC-FOSDEM Adarsh Sha h Engineering Leader, Coach, Hands-on Architec t Independent Consultan t @shahadarsh 
 https://shahadarsh.com