GitLab Runners Private

Overview

This Terraform code creates a GitLab runner on AWS EC2.

• Use EC2 instance to host the runner.
• The EC2 will launch in private subnets. Not exposed to the public internet.
• The EC2 also be able to use SSM to connect to the instance.
• The EC2 instance size is defined in terraform.tfvars file.
• Use IAM role and instance profile to manage permissions.
• Autoscale the runner to 3 instances during business hours.
• Scale to 0 instances when outside business hours.
• Business hours are defined in terraform.tfvars file.
• The runner tags are defined in terraform.tfvars file.
• Use CloudWatch to monitor the runner.

Prerequisites

• Terraform CLI
• AWS CLI
• GitLab Runner token

Architecture

IAM

The file terraform-gitlab-runner-policy.json will guide you to create the IAM policy for this project.

Usage

The Gitlab URL and runner token can be found in the Gitlab instance under Settings > CI / CD > Runners settings.

Don't put the runner token in the terraform.tfvars file. Use the -var flag to set the runner token and store token in environment variable.

1. Set the environment variables.
2. Run terraform init.
3. Run terraform plan -var="gitlab_url=xxxxx" -var="gitlab_runner_token=xxxxx" -out=tfplan.
4. Run terraform apply tfplan.

Variables

• aws_region: AWS region.
• environment: Environment name.
• instance_type: EC2 instance type.
• business_hours_start: Business hours start time (GMT).
• business_hours_end: Business hours end time (GMT).
• gitlab_url: GitLab instance URL.
• gitlab_runner_token: GitLab runner registration token.
• runner_tags: Runner tags.
• cloudwatch_log_group_name: CloudWatch log group name.