IaC: DCOS

This terraform script will setup the DCOS cluster in AWS.

• Bootstrap Node (CentOS)
• Master and Agent Nodes (CoreOS)
• Private subnet
• Public subnet
• Internet gateway

Pre-requisites

• With IaC-Manager or skip to manual steps

  • Use IaC-manager to create a manager node. Then SSH into the manager node and perform the steps for installation.

• Manual steps

  • An IAM account with privileges mentioned here.
  • An existing infrastructure with a VPC, Subnet and instance from where this terraform can be run. We need the following information prior to starting the script.
    • vpc_id
    • key_pair_name We have an Iac-manager which can do this task.
  • Install terraform in the machine from here. Terraform v0.7.0 or above is required.

• Public Key Access with Agent support/ Agent Forwarding:

  ssh-add <key_pair_name>.pem
  ssh -A centos@<manager_public_ip>

• Hosted zone in AWS Route53 for your domain name. This is required to create a record for creating a friendly dns name for the load balancer.

  • If you do not want to create a dns name for load balancer, remove the aws_route53_record resource from elb-master.tf

• "Accept Software Terms" of aws marketplace for CentOS or CoreOS.

Steps to install DCOS

• Export AWS credentials as bash variables

export AWS_ACCESS_KEY_ID="anaccesskey" 
export AWS_SECRET_ACCESS_KEY="asecretkey"
export AWS_DEFAULT_REGION="ap-northeast-1"

• Clone this repo.
• Copy your AWS ssh key into current dir.
• cp terraform.dummy terraform.tfvars
• If you are using IaC-Manager, run cat ~/terraform.out >> ~/IaC-dcos/terraform.tfvars once.
• Modify params in terraform.tfvars
• (Optional) Modify params in variable.tf to change default values including subnet or add AMI accordingly to your aws region
• Run terraform plan to see the plan to execute.
• Run terraform apply to run the scripts.
• You may have prod/dev/stage configurations in terraform.tfvars.{prod/dev/stage} files (already ignored by .gitignore).

Notes

• The AWS key name, AWS key path, VPC, Subnet, Security Group will be updated to terraform.dummy if the installation is done by IaC-Manager.
• If unable to perform terraform destroy, instance profile can be removed using aws cli only. aws iam list-instance-profiles | grep InstanceProfileName aws iam delete-instance-profile --instance-profile-name ${var.pre_tag}_s3_profile_master_${var.post_tag} aws iam delete-instance-profile --instance-profile-name ${var.pre_tag}_s3_profile_agents_${var.post_tag} aws iam delete-instance-profile --instance-profile-name ${var.pre_tag}_s3_profile_public_agent_${var.post_tag}

Contributing

1. Make a feature branch: git checkout -b your-username/your-feature
2. Follow Terraform Style Guide
3. Make your feature. Keep things tidy so you have one commit per self-contained change (squashing can help).
4. Push your branch: git push -u origin your-username/your-feature
5. Open GitHub to the repo, under "Your recently pushed branches", click Pull Request for your-username/your-feature.

Be sure to use a separate feature branch and pull request for every self-contained feature. If you need to make changes from feedback, make the changes in place rather than layering on commits (use interactive rebase to edit your earlier commits). Then use git push --force origin your-feature to update your pull request.