Full script is available at https://github.com/JaydeepUniverse/terraform/tree/master/aws/efs Prerequisites - Along with EFS creation we'd need to mount on subnet as well where we would going to use it, hence To get existing subnet details follow below steps Import existing subnet details by adding below code to main.tf and resource "aws_subnet" "subnet-aaa" { } resource "aws_subnet" "subnet-aaa" { } Run terraform import command - terraform import aws_subnet.subnet-aaa subnet-aaa terraform import aws_subnet.subnet-aaa subnet-aaa Then add subnet values from terraform.tfstateto main.tf else terraform will add/remove parameters accordingly for the same subnet ex. ...