Ondrej Sikaondrej@sika.io@ondrejsika

LinuxDays 2019

TerraformInfrastructure as a code

About me - Ondrej Sika

I'm DevOps consultant and lecturer.

I'm helping companies to setup DevOps. That means for them to focus on their product, faster & more reliable delivery new features to production and stop wasting time for example on deployments and infrastructure.

We want Git versioned

- Source Code- Environments (Dockerfiles)- Configuration (Nginx, …)- Deployments (Kubernetes)- Infrastructure?

How we handle infrastructure?

- Physical servers - manually- Virtual servers - manually- Cloud - manually- Cloud - as a code - Terraform

Terraform

What is Terraform?

Terraform is a tool for managing infrastructure as code

You can version your infrastructure in Git, create resources from pull requests or fork infrastructure you like.

Terraform

- Designed for infrastructure management- Provide declarative way how to define your infrastructure- Support removing resources (has state)- Help you to evolve infrastructure save & predictable way- Work with all major clouds (AWS, Azure, …)- Open Source (18 000 stars on Github)- Can predict costs (Terraform Enterprise)

Why Terraform? and not Ansible, Puppet, ...

Terraform is better with Ansible, Puppet, ...

- Terraform is not a configuration management tool, Ansible or Puppet do it and do it pretty good

- Terraform work with configuration management tool- Terraform creates infrastructure and run CM tool for

setting up the resources

How Terraform works

Terraform compare actual infrastructure (stored in local or remote state) and infrastructure you want (in .tf files).

Then apply (create, update or remove) the differences.

Configuration Language

Providers

A provider is responsible for understanding API interactions and exposing resources.

Providers generally are an IaaS (e.g. AWS, GCP, Azure, OpenStack) or SaaS services (e.g. CloudFlare, Gitlab).

Resources

Terraform is used to create, manage, and update infrastructure resources such as physical machines, VMs, network switches, containers, and more. Almost any infrastructure type can be represented as a resource in Terraform.

Data Sources

Data sources allow data to be fetched or computed for use elsewhere in Terraform configuration.

Use of data sources allows a Terraform configuration to make use of information defined outside of Terraform, or defined by another separate Terraform configuration.

Modules

A module is a container for multiple resources that are used together.

Backends

A "backend" in Terraform determines how state is loaded and how an operation such as apply is executed. This abstraction enables non-local file state storage, remote execution, etc.

Why remote state / backend?

- Working in a team- Remote operations (CI/CD)

Terraform CLI

Terraform CLI

- terraform init - download plugins & setup modules- terraform plan - show & prepare changes of

infrastructure- terraform apply - apply new version of infrastructure- terraform destroy - destroy your infrastructure

Demo Time

ondrej-sika.cz/repozitare/#terraform

Thank you & Questions

Ondrej Sika

email: ondrej@sika.iowww: https://ondrej-sika.cztwitter: @ondrejsikalinkedin: /in/ondrejsika/

Slides: https://sika.link/linuxdays2019