AWS Elastic Container Service (ECS) Terraform configuration

Terraform configuration which creates EC2 lauch type ECS resources on AWS together with postgres RDS.

Usage

You will first need to install terraform and configure aws cli profile.

brew install terraform

By default both, free tier and default configuration use default profile. If you want to specify different profile you can to that by specifiying variables on the commandline using -var option

terraform apply -var-file="free-tier.tfvars" -var="profile=jkobejs"

terraform apply -var="profile=jkobejs"

Free tier

This configuration creates working ECS cluster with RDS using AWS Free Tier offering.

To create free tier infrastructure run

terraform apply -var-file="free-tier.tfvars"

command. It will create virtual private network in eu-central-1 region that contains:

• 2 availability zones
• 2 subnets (public, database)
• application load balancer (public subnet)
• auto scaling group (public subnet)
• RDS (database subnet)

Besides VPC command will create:

• ECS cluster
• container instances
• user ecs task and servic

Using this command auto scaling group that contains EC2 container intances will be placed in public subnet. Usually desired place to place container instances would be private subnet. Since container instances need to communicate with ECS cluster over internet only way to satify this using Free Tier resources is to put it in public subnet because NAT gateways are not part of Free Tier.

Default (you will be billed for some resources)

By default terraform

terraform apply

command will create virtual private network in eu-central-1 region that contains:

• 2 availability zones
• 3 subnets (public, private, database)
• application load balancer (public subnet)
• NAT gateway per availability zone (public subnet)
• auto scaling group (private subnet)
• RDS (database subnet)

Besides VPC command will create:

• ECS cluster
• container instances
• user ecs task and service

Requirements

No requirements.

Providers

No provider.

Inputs

Name	Description	Type	Default	Required
asg_desired_capacity	The number of Amazon EC2 instances that should be running in the group	number	0	no
asg_max_size	The maximum size of the auto scale group	number	1	no
asg_min_size	The minimum size of the auto scale group	number	0	no
asg_wait_for_capacity_timeout	Setting this will cause Terraform to wait for exactly this number of healthy instances in all attached load balancers on both create and update operations. Takes precedence over min_elb_capacity behavior.	number	0	no
azs	Availability zones, at least 2 availability zones should be specified	list	[ "eu-central-1a", "eu-central-1b" ]	no
cidr	VPC's cidr	string	"10.1.0.0/16"	no
database_subnets	Subnet in which database services will be deployed	list	[ "10.1.13.0/24", "10.1.23.0/24" ]	no
db_instance_type	Database instance type	string	"db.t2.micro"	no
db_name	Database name	string	"master"	no
db_password	Database password	string	"ChangeMe!"	no
db_username	Database username	string	"db_user"	no
ec2_instance_type	EC2 instance type	string	"t2.micro"	no
enable_nat_gateway	Flag that determines if NAT gateway will be created	bool	true	no
environment	Environment in which resources will be created	string	"dev"	no
name	Base name for all resources	string	"ecs-terraform"	no
one_nat_gateway_per_az	Flag that determines if one NAT gateway will be created per AZ	bool	true	no
private_subnets	Subnet in which private services will be deployed	list	[ "10.1.12.0/24", "10.1.22.0/24" ]	no
profile	Named profile, more on https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-profiles.html	string	"default"	no
public_container_instances	Flag that determines if container instances are in public subnet (useful in free tier)	bool	false	no
public_subnets	Subnet in which public services will be deployed	list	[ "10.1.11.0/24", "10.1.21.0/24" ]	no
region	AWS region	string	"eu-central-1"	no

Outputs

Name	Description
alb_arn	ALB arn
alb_dns_name	ALB DNS name
alb_ecs_role_arn	ALB role
alb_traget_group_arns	ALB target groups arns
asg_arn	ASG arn
ecr_arn	ECR arn
ecr_id	ECR id
ecs_cluster_arn	ECS cluster arn
ecs_cluster_id	ECS cluster id
ecs_cluster_name	ECS cluster name
erc_url	ECR url
rds_arn	RDS arn
rds_host	RDS host
vpc_id	VPC id

Authors

Module managed by jkobejs

License

Apache 2 Licensed. See LICENSE for full details.