Terraform for AWS - example

Terraform example for one RDS instance & One EC2 instance ;

Pre-requisies

• A working Terraform version > 0.12 in $PATH
• I have tried the new terraform v0.12x syntax where possible
• A working Ansible installation locally (recent version)
• Working valid AWS credentials in $HOME/.aws/
• A AWS VPC pre-created before running terraform here
• The file "terraform.tfvars", in root folder here, should contain these four variables

region     = "us-west-1"
vpc_id     = "vpc-nhg20ks8"
kms_key_id   = ""
rds_endpoint = ""

• You need to generate a ssh keypair named as id_rsa and id_rsa.pub in ./modules/webserver folder. Don't set a password to the priv key ;

    ssh-keygen -t rsa

• You need to fix permissions on id_rsa.pub

    chmod 600 id_rsa.pub

• Modify vars.tf, in root folder, if required

Caution - read & understand the impact of kms module. Takes 7 days to remove a key after destroy

Git clone or zip download this repo. Then run ;

    * terraform init
    * terraform plan
    * terraform apply

Functionalities demonstrated in this example

• kms key created

• random string generated for rds password

• ssm parameter added for rds password

• securitygroup created for rds postgres

• subnetgroupname created for rds

• rds postgres instance crated

• ec2 instance created

• sshkey for ec2 instance created

• role for ec2 instance created

• securitygroup for ec2 instance created

• Ansible installs nginx & php-fpm and changes them to custom config

• RDS credentials are retrieved from ssm and stored on server in /tmp

• (If required, can add a delete step for those creds after configuring php app)

• Ansible copies over a custom tiny index.php that connects to postgres

• Index.php creates a table, inserts a oneliner record and retrieves it from db to render html

• Go to the IP-Address or Hostname of EC2 instance to see index.php working with postgres

• TODO: I would rather do the webpage with python but a single tiny PHP page achieves the same goal that a MVC framwork of flask or django would

• TODO: Several cleanups and improvements