infrastructure-notes/Terraform Notes.md

Terraform Notes.md

Hashicorp Terraform is used to deploy AWS resources by writing code.

TFswitcher

• Introduction to tfswitch - Main site
• tfswitch Github

• Installation

• Introduction to tgswitch - Main site

• tgswitch Github

  brew install warrensbox/tap/tfswitch
  brew install warrensbox/tap/tgswitch
  

If there is a file that has a terraform version specified, running tfswitch will automatically switch to that version.

Debug

06/2020

Enable debug
export TF_LOG=DEBUG
export TF_LOG_PATH=./terraform.log

Disable debug
export TF_LOG=

Workspaces

05/2020

---

#workspaces are being used to break up environments. 
terraform workspace list
terraform workspace select test


#Strange errors? Unexpected results? try this
rm .terraform
terraform init

#State issues
terraform state show aws_ami.msoc_base
terraform refresh -target=data.aws_ami.msoc_base

Terraform also has a DynamoDB State lock (msoc-terraform-lock). This will prevent terraform state breakage.

To manually remove the lock: Terraform CLI - Command: force-unlock

---

View TF code Terraform AWS modules Github

---

Modules

We are using the aws ec2-instance module

• Terrform Registry Modules

• Terraform module which creates EC2 instance(s) on AWS - v2.13.0

• Terraform AWS Module Github

var.something means this is a module that needs the variable to run. Your code will fill the variable. data is a read-only terrafom object that queries provider or generates something on the localhost locals are variables that can refer to variables or other locals variables - expecting data from somewhere else. provider instance of the API

Some files are symlinks.

ln -s ../common/variables.tf variables.tf
ln -s ../amis.tf amis.tf
ln -s ../../../../prod/aws-us-gov/mdr-prod-c2/090-instance-vault/README.md README.md

---

IAM Role

get this error?

aws_iam_policy.nga_instance_policy: Error creating IAM policy nga_instance_tag_read: AccessDenied:

add this

  provider = "aws.iam_admin"

---

In terraform .tf files when the self = true. That is for putting the security group into itself. e.g. add the security group to the security groups rules.

the Terraform is setup in folders. each folder is a project and apply should be run in the folder. Common is the execption as some of the projects are dependent on that folder.

Role and Policy have to be done in the IAM terraform

iam_data.tf

02-msoc_vpc/lambda.tf with security groups

terraform plan -target=
terraform plan -target=module.sensu_go_server.aws_instance.this -target=module.sensu_go_server.aws_route53_record.private

terraform apply -target=module.sensu_server.aws_route53_record.private -target=module.sensu_server.aws_instance.this

terraform apply -target=aws_security_group_rule.outbound_to_sensu -target=module.sensu_servers_sg.aws_security_group_rule.ingress_with_cidr_blocks[0] -target=module.sensu_servers_sg.aws_security_group_rule.ingress_with_cidr_blocks[1]

terraform apply -target=module.vpc_default_security_groups.aws_security_group_rule.typical_host_outbound_to_sensu_8081 -target=aws_security_group_rule.vault_server_to_sensu -target=module.vpc_default_security_groups.aws_security_group_rule.typical_host_outbound_to_sensu_5672


terraform apply -target=module.afs_cluster.module.vpc_default_security_groups.aws_security_group_rule.typical_host_outbound_to_sensu_5672 -target=module.afs_cluster.module.vpc_default_security_groups.aws_security_group_rule.typical_host_outbound_to_sensu_8081

Updating to TF13 and AWS 3

We were generally using AWS 3 as soon as it came out. Now, the aws provider version is specified in xdr-terraform-live/terragrunt.hcl.

Updating from TF12 to TF13 had no major issues. If you run into a module that isn't functioning first try:

terragrunt init --reconfigure
terragrunt apply

If it's an issue with a provider, you may need to add a required_providers tag to one of your files (e.g. providers-okta.tf)that looks like this:

terraform {
  required_providers {
    okta = {
      source  = "oktadeveloper/okta"
    }
  }
}