HashiCorp User Group Oslo - initial commit meetup about Terraform by Anton Babenko - 20.11.2017

1. HashiCorp User Group Oslo
20.11.2017
https://meetup.com/Oslo-HashiCorp-User-Group/

2. Food sponsor:
Agenda - initial commit
1. About this user group
2. Terraform questions & problems
3. Terraform Q&A
Want to be a speaker?
Send an email - anton@antonbabenko.com

3. About this user group
This HashiCorp User Group Oslo is the place
where interested people gather once every
couple months to learn from each other about
HashiCorp products— what we do, how we do
it, and how can we do it differently. While I
generally strive to make such meetups
interesting for the participants, I am often
against the repetitive talks which can be found
online easily.
Latest editition: 20.11.2017
Anton Babenko,
CEO at Betajob
linkedin.com/in/antonbabenko
github.com/antonbabenko
anton@antonbabenko.com
Keywords: All-5 AWS certified, DevOps,
infrastructure as code, automation, open-source,
community member and events organiser,
Terraform modules, solution architectures,
serverless.
About me

5. Featuring...
Read also -
https://www.hashicorp.com/tao-of-hashicorp

6. Featuring...
Write, Plan, and Create Infrastructure as Code

7. Terraform 101 (main.tf)
provider "aws" { region = "eu-west-1" }
resource "random_pet" "bucket" {}
resource "aws_s3_bucket" "app" {
bucket = "hi-${random_pet .bucket. id}"
website {
index_document = "index.html"
}
}
data "template_file" "index" {
template = "${file("index.html")}"
vars {
BUCKET = "${aws_s3_bucket .app.website_endpoint }"
}
}
resource "aws_s3_bucket_object" "object" {
bucket = "${aws_s3_bucket .app.id}"
key = "index.html"
content = "${data. template_file .index.rendered }"
etag = "${md5(data. template_file .index.rendered )}"
content_type = "text/html"
acl = "public-read"
}
output "app_website_endpoint" {
value = "${aws_s3_bucket .app.website_endpoint }"
}
index.html can access:
${BUCKET}
$ terraform init
$ terraform plan
$ terraform apply
Apply complete! Resources: 3 added, 0
changed, 0 destroyed.
Outputs:
app_website_endpoint =
hi-feasible-basilisk.s3-website-eu-west-1.a
mazonaws.com

8. Frequent Terraform Questions (FTQ)

9. Why Terraform and not AWS CloudFormation/Azure
ARM templates/Google Cloud Deployment
Manager?
Terraform manages 70+ providers, has easier syntax (HCL), has native support for modules
and remote states, has team-work features. Terraform is an open-source project (640 - AWS
provider, 1100 - core).
https://medium.com/@piotrgospodarek/cloudformation-vs-terraform-990318d6a7de
https://cloudonaut.io/cloudformation-vs-terraform/
https://www.slideshare.net/AntonBabenko/continuously-delivering-infrastructure-using-terrafo
rm-and-packer-training-material

10. Tord P.: What is the point of using these tools if
you’re running AWS only, e.g. isn’t Terraform just a
an unnecessary abstraction, why not stick to
CloudFormation?
Terraform manages 70+ providers, has easier syntax (HCL), has native support for modules
and remote states, has team-work features. Terraform is an open-source project.
Abstractions (primitives and modules) are necessary and easily available (Terraform
Registry).

11. What are the most common tools/solutions out there?
● Terraform Module Registry to discover modules for common infrastructure
configurations for any provider - https://registry.terraform.io/ (I maintain verified AWS
modules there)
● Thin wrapper for Terraform that provides extra tools for working with multiple Terraform
modules - https://github.com/gruntwork-io/terragrunt
● Terraform linter for detecting errors that can not be detected by `terraform plan` -
https://github.com/wata727/tflint
● Terraform version manager - https://github.com/kamatama41/tfenv
This list is much longer, really…

12. How to handle secrets in Terraform?
1. Can you accept secrets to be saved in state file in plaintext? Probably not.
a. AWS IAM password & access secret keys - use PGP as keybase.io
b. AWS RDS - set dummy password and change after DB is created
c. AWS RDS - use iam_database_authentication_enabled = true
d. EC2 instance user-data + AWS KMS
2. Other options:
a. Secure remote state location (S3 bucket policy, KMS key)

13. How to get started?
1. Install and getting started - https://www.terraform.io/intro/getting-started/install.html
2. Get infrastructure modules from Terraform Registry. For example, AWS modules -
https://registry.terraform.io/modules/terraform-aws-modules
3. Follow instructions in README.md, check examples, open issues and pull requests.

14. Frequent Terraform Problems (FTP)

15. Upgraded Terraform version, and there is a breaking
bug, so I want to rollback, but I can’t because state
file has been upgraded already.
● State file should be versioned (!), download previous version of state file, run “terraform
state push old_version.tfstate”
● Lock terraform version, lock module and providers version (new in 0.11)
● Read upgrade guides and CHANGELOG.md files:
○ https://www.terraform.io/upgrade-guides/0-11.html
○ https://github.com/hashicorp/terraform/blob/master/CHANGELOG.md
○ https://github.com/terraform-providers/terraform-provider-aws/blob/master/CHANG
ELOG.md

16. What is your Terraform question or problem?
PS: Maybe something about testing? Versioning? Code structure? Working as a
team? CI/CD? Automation? Integration with other tools? https://modules.tf/ ? Code
generation? Missing tools/features? Syntax sugar (features and types of
variables)? How to contribute?

17. Thanks!
https://www.terraform.io/
https://github.com/terraform-aws-modules/
https://www.slideshare.net/AntonBabenko/continuously-delivering-infrastructure-using-terrafo
rm-and-packer-training-material
https://github.com/arun-gupta/kubernetes-aws-workshop/issues/135 - "Add Terraform
template for cluster creation”