Conditionally create EFS for ECS cluster

* Conditionally creates an EFS file system. This can be used as a shared
  filesystem between the container instances.
* If the ECS cluster has been enabled, it will mount the EFS file system
  onto the instances at `/mnt/efs`
* A list of directories can be provided, which will be created within
  the EFS file system
* A security group is added that allows access from the ECS container
  instances security group. A rule is also added to the ECS container
  instances securit group to allow outbound to the EFS security group.

README.md

@@ -33,6 +33,8 @@ This project creates and manages resources within an AWS account for infrastruct
 | [aws_cloudwatch_log_group.infrastructure_vpc_flow_logs](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudwatch_log_group) | resource |
 | [aws_default_network_acl.infrastructure](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/default_network_acl) | resource |
 | [aws_ecs_cluster.infrastructure](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/ecs_cluster) | resource |
+| [aws_efs_file_system.infrastructure_ecs_cluster](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/efs_file_system) | resource |
+| [aws_efs_mount_target.infrastructure_ecs_cluster](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/efs_mount_target) | resource |
 | [aws_eip.infrastructure_nat](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/eip) | resource |
 | [aws_flow_log.infrastructure_vpc_flow_logs_cloudwatch](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/flow_log) | resource |
 | [aws_flow_log.infrastructure_vpc_flow_logs_s3](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/flow_log) | resource |
@@ -93,12 +95,15 @@ This project creates and manages resources within an AWS account for infrastruct
 | [aws_s3_bucket_server_side_encryption_configuration.infrastructure_logs](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/s3_bucket_server_side_encryption_configuration) | resource |
 | [aws_s3_bucket_versioning.infrastructure_logs](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/s3_bucket_versioning) | resource |
 | [aws_security_group.infrastructure_ecs_cluster_container_instances](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
+| [aws_security_group.infrastructure_ecs_cluster_efs](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_dns_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_dns_udp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_https_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_https_udp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
+| [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_nfs_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_ingress_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_ingress_udp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
+| [aws_security_group_rule.infrastructure_ecs_cluster_efs_ingress_nfs_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_sns_topic.infrastructure_ecs_cluster_autoscaling_lifecycle_termination](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/sns_topic) | resource |
 | [aws_sns_topic_subscription.ecs_cluster_infrastructure_draining_autoscaling_lifecycle_termination](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/sns_topic_subscription) | resource |
 | [aws_subnet.infrastructure_private](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/subnet) | resource |
@@ -115,7 +120,12 @@ This project creates and manages resources within an AWS account for infrastruct
 |------|-------------|------|---------|:--------:|
 | <a name="input_aws_profile_name_route53_root"></a> [aws\_profile\_name\_route53\_root](#input\_aws\_profile\_name\_route53\_root) | AWS Profile name which is configured for the account in which the root Route53 Hosted Zone exists. | `string` | n/a | yes |
 | <a name="input_aws_region"></a> [aws\_region](#input\_aws\_region) | AWS region in which to launch resources | `string` | n/a | yes |
+| <a name="input_ecs_cluster_efs_directories"></a> [ecs\_cluster\_efs\_directories](#input\_ecs\_cluster\_efs\_directories) | ECS cluster EFS directories to create | `list(string)` | n/a | yes |
+| <a name="input_ecs_cluster_efs_infrequent_access_transition"></a> [ecs\_cluster\_efs\_infrequent\_access\_transition](#input\_ecs\_cluster\_efs\_infrequent\_access\_transition) | ECS cluser EFS IA transiton in days. Set to 0 to disable IA transition. | `number` | n/a | yes |
+| <a name="input_ecs_cluster_efs_performance_mode"></a> [ecs\_cluster\_efs\_performance\_mode](#input\_ecs\_cluster\_efs\_performance\_mode) | ECS cluser EFS performance mode | `string` | n/a | yes |
+| <a name="input_ecs_cluster_efs_throughput_mode"></a> [ecs\_cluster\_efs\_throughput\_mode](#input\_ecs\_cluster\_efs\_throughput\_mode) | ECS cluser EFS throughput mode | `string` | n/a | yes |
 | <a name="input_enable_infrastructure_ecs_cluster"></a> [enable\_infrastructure\_ecs\_cluster](#input\_enable\_infrastructure\_ecs\_cluster) | Enable creation of infrastructure ECS cluster, to place ECS services | `bool` | n/a | yes |
+| <a name="input_enable_infrastructure_ecs_cluster_efs"></a> [enable\_infrastructure\_ecs\_cluster\_efs](#input\_enable\_infrastructure\_ecs\_cluster\_efs) | Conditionally create and mount EFS to the ECS cluster instances | `bool` | n/a | yes |
 | <a name="input_enable_infrastructure_route53_hosted_zone"></a> [enable\_infrastructure\_route53\_hosted\_zone](#input\_enable\_infrastructure\_route53\_hosted\_zone) | Creates a Route53 hosted zone, where DNS records will be created for resources launched within this module. | `bool` | n/a | yes |
 | <a name="input_environment"></a> [environment](#input\_environment) | The environment name to be used as part of the resource prefix | `string` | n/a | yes |
 | <a name="input_infrastructure_dockerhub_email"></a> [infrastructure\_dockerhub\_email](#input\_infrastructure\_dockerhub\_email) | Dockerhub email | `string` | n/a | yes |

ec2-userdata/ecs-instance.tpl

@@ -28,3 +28,15 @@ fi
 sudo yum install -y \
   jq \
   rsync
+
+# EFS
+%{if efs_id != "" ~}
+sudo mkdir -p /mnt/efs
+sudo yum install -y nfs-utils
+sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 ${efs_id}.efs.${region}.amazonaws.com:/ /mnt/efs
+echo '${efs_id}.efs.${region}.amazonaws.com:/ /mnt/efs nfs4 nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 0 0' | sudo tee -a /etc/fstab
+%{if efs_dirs != "" ~}
+cd /mnt/efs
+mkdir -p ${efs_dirs}
+cd ..
+%{~ endif}%{endif}

ecs-cluster-infrastructure.tf

@@ -101,6 +101,18 @@ resource "aws_security_group_rule" "infrastructure_ecs_cluster_container_instanc
   security_group_id = aws_security_group.infrastructure_ecs_cluster_container_instances[0].id
 }
 
+resource "aws_security_group_rule" "infrastructure_ecs_cluster_container_instances_egress_nfs_tcp" {
+  count = local.enable_infrastructure_ecs_cluster && local.enable_infrastructure_ecs_cluster_efs ? 1 : 0
+
+  description              = "Allow NFS tcp outbound to EFS security group"
+  type                     = "egress"
+  from_port                = 2049
+  to_port                  = 2049
+  protocol                 = "tcp"
+  source_security_group_id = aws_security_group_rule.infrastructure_ecs_cluster_efs_ingress_nfs_tcp[0].id
+  security_group_id        = aws_security_group.infrastructure_ecs_cluster_container_instances[0].id
+}
+
 resource "aws_iam_role" "infrastructure_ecs_cluster" {
   count = local.enable_infrastructure_ecs_cluster ? 1 : 0
 

efs-infrastructure.tf

@@ -0,0 +1,48 @@
+resource "aws_efs_file_system" "infrastructure_ecs_cluster" {
+  count = local.enable_infrastructure_ecs_cluster_efs ? 1 : 0
+
+  encrypted        = local.infrastructure_kms_encryption
+  kms_key_id       = local.infrastructure_kms_encryption ? aws_kms_key.infrastructure[0].id : null
+  performance_mode = local.ecs_cluster_efs_performance_mode
+  throughput_mode  = local.ecs_cluster_efs_throughput_mode
+
+  dynamic "lifecycle_policy" {
+    for_each = local.ecs_cluster_efs_infrequent_access_transition != 0 ? [1] : []
+    content {
+      transition_to_ia                    = local.ecs_cluster_efs_infrequent_access_transition
+      transition_to_primary_storage_class = "AFTER_1_ACCESS"
+    }
+  }
+}
+
+resource "aws_efs_mount_target" "infrastructure_ecs_cluster" {
+  for_each = local.enable_infrastructure_ecs_cluster_efs ? local.infrastructure_vpc_network_enable_private ? [
+    for subnet in aws_subnet.infrastructure_private : subnet.id
+    ] : local.infrastructure_vpc_network_enable_public ? [
+    for subnet in aws_subnet.infrastructure_private : subnet.id
+  ] : [] : []
+
+  file_system_id  = aws_efs_file_system.infrastructure_ecs_cluster[0].id
+  subnet_id       = each.value
+  security_groups = local.enable_infrastructure_ecs_cluster ? [aws_security_group.infrastructure_ecs_cluster_efs[0].id] : []
+}
+
+resource "aws_security_group" "infrastructure_ecs_cluster_efs" {
+  count = local.enable_infrastructure_ecs_cluster_efs && local.enable_infrastructure_ecs_cluster ? 1 : 0
+
+  name        = "${local.resource_prefix}-infrastructure-ecs-cluster-efs"
+  description = "Infrastructure ECS cluster EFS"
+  vpc_id      = aws_vpc.infrastructure[0].id
+}
+
+resource "aws_security_group_rule" "infrastructure_ecs_cluster_efs_ingress_nfs_tcp" {
+  count = local.enable_infrastructure_ecs_cluster_efs && local.enable_infrastructure_ecs_cluster ? 1 : 0
+
+  description              = "Allow ECS instances access to EFS (NFS) tcp"
+  type                     = "ingress"
+  from_port                = 2049
+  to_port                  = 2049
+  protocol                 = "tcp"
+  source_security_group_id = aws_security_group.infrastructure_ecs_cluster_container_instances[0].id
+  security_group_id        = aws_security_group.infrastructure_ecs_cluster_efs[0].id
+}

locals.tf

@@ -114,9 +114,20 @@ locals {
       dockerhub_token                   = local.infrastructure_dockerhub_token,
       dockerhub_email                   = local.infrastructure_dockerhub_email,
       docker_storage_size               = local.infrastructure_ecs_cluster_ebs_docker_storage_volume_size
+      efs_id = local.enable_infrastructure_ecs_cluster_efs && (
+        local.infrastructure_vpc_network_enable_private || local.infrastructure_vpc_network_enable_public
+      ) ? aws_efs_file_system.infrastructure_ecs_cluster[0].id : "",
+      region   = local.aws_region,
+      efs_dirs = join(" ", local.ecs_cluster_efs_directories)
     })
   )
 
+  enable_infrastructure_ecs_cluster_efs        = var.enable_infrastructure_ecs_cluster_efs && local.infrastructure_vpc
+  ecs_cluster_efs_performance_mode             = var.ecs_cluster_efs_performance_mode
+  ecs_cluster_efs_throughput_mode              = var.ecs_cluster_efs_throughput_mode
+  ecs_cluster_efs_infrequent_access_transition = var.ecs_cluster_efs_infrequent_access_transition
+  ecs_cluster_efs_directories                  = var.ecs_cluster_efs_directories
+
   default_tags = {
     Project        = local.project_name,
     Infrastructure = local.infrastructure_name,

variables.tf

@@ -264,3 +264,28 @@ variable "infrastructure_ecs_cluster_max_instance_lifetime" {
   description = "Maximum lifetime in seconds of an instance within the ECS cluster"
   type        = number
 }
+
+variable "enable_infrastructure_ecs_cluster_efs" {
+  description = "Conditionally create and mount EFS to the ECS cluster instances"
+  type        = bool
+}
+
+variable "ecs_cluster_efs_performance_mode" {
+  description = "ECS cluser EFS performance mode"
+  type        = string
+}
+
+variable "ecs_cluster_efs_throughput_mode" {
+  description = "ECS cluser EFS throughput mode"
+  type        = string
+}
+
+variable "ecs_cluster_efs_infrequent_access_transition" {
+  description = "ECS cluser EFS IA transiton in days. Set to 0 to disable IA transition."
+  type        = number
+}
+
+variable "ecs_cluster_efs_directories" {
+  description = "ECS cluster EFS directories to create"
+  type        = list(string)
+}