AWS EFS with Terraform

Friday, 10 March 2023

AWS EFS with Terraform

The minimal aws_efs_file_system | Resources | hashicorp/aws | Terraform Registry resource example is:

resource "aws_efs_file_system" "my-app-data-efs" {
tags = {
Name = "my-app-data-efs"
}
}

In AWS Console, we can go to Amazon EFS >> File systems and verify that it's created. Its attributes are:

Name: my-app-data-efs

File system ID: fs-1d130ce4a92769f59

Encrypted: Unencrypted

Total size: 6.00 KiB

Size in Standard / One Zone: 6.00 KiB

Size in Standard-IA / One Zone-IA: 0 Bytes

Provisioned Throughput (MiB/s): -

File system state: Available

Creation time: Thu, 09 Mar 2023 10:41:55 GMT

Availability Zone: Standard

Performance mode: General Purpose

Throughput mode: Bursting
Lifecycle management:

Transition into IA: None

Transition out of IA: None

Availability zone: Standard

Automatic backups: Disabled
Encrypted: No
File system state: Available
DNS name: No mount targets available

It will have no Access points and no Mount targets defined:

To provide mount target, we need to use aws_efs_mount_target | Resources | hashicorp/aws | Terraform Registry. Required attributes are EFS (for which we want to create mount target) and subnet (in which we want this mount target to be):

resource "aws_efs_mount_target" "my-app-data-efs-mt" {
file_system_id = aws_efs_file_system.my-app-data-efs.id
subnet_id = "subnet-14321c874d6d35c6a"
}

terraform plan output:

Terraform will perform the following actions:

# aws_efs_mount_target.my-app-data-efs-mt will be created
+ resource "aws_efs_mount_target" "my-app-data-efs-mt" {
      + availability_zone_id   = (known after apply)
      + availability_zone_name = (known after apply)
      + dns_name               = (known after apply)
      + file_system_arn        = (known after apply)
      + file_system_id         = "fs-1d130ce4a92769f59"
      + id                     = (known after apply)
      + ip_address             = (known after apply)
      + mount_target_dns_name = (known after apply)
      + network_interface_id   = (known after apply)
      + owner_id               = (known after apply)
      + security_groups        = (known after apply)
      + subnet_id              = "subnet-14321c874d6d35c6a"
    }

Plan: 1 to add, 0 to change, 0 to destroy.

After applying this change, we can check again Network settings for EFS where we'll see that mount target is now available: