Book Image

Getting Started with Terraform

By : Kirill Shirinkin
Book Image

Getting Started with Terraform

By: Kirill Shirinkin

Overview of this book

Terraform is a tool used to efficiently build, configure, and improve production infrastructure. It can manage existing infrastructure as well as create custom in-house solutions. This book shows you when and how to implement infrastructure as a code practices with Terraform. It covers everything necessary to set up complete management of infrastructure with Terraform, starting with the basics of using providers and resources. This book is a comprehensive guide that begins with very small infrastructure templates and takes you all the way to managing complex systems, all using concrete examples that evolve over the course of the book. It finishes with the complete workflow of managing a production infrastructure as code – this is achieved with the help of version control and continuous integration. At the end of this book, you will be familiar with advanced techniques such as multi-provider support and multiple remote modules.
Table of Contents (15 chapters)
Getting Started with Terraform
About the Author
About the Reviewer
Customer Feedback

Refreshing infrastructure

It could be that someone updated the resource managed by Terraform manually, via AWS API or AWS Management Console. If changed attribute is specified inside the template, then you can fix it by running the terraform apply command--given that Terraform templates are the source of truth when it comes to the state of the infrastructure. But if this attribute is not managed by Terraform template, then you might still want it to be reflected in your state file. That's when the terraform refresh command comes to the rescue.

Apply the template and then go to AWS Console. Open the VPC section and find the VPC Terraform created. Right-click on this VPC and choose Edit DNS Hostnames. Then change DNS Hostnames to Yes:

Now head back to your console and execute the terraform refresh command. Open the terraform.tfstate file and verify that the change in the state file happened as expected:

 "aws_vpc.my_vpc": { 
                    "type": "aws_vpc",