aws_ssm_association

resource "aws_security_group" "tf_test_foo" {
  name = "tf_test_foo"
  description = "foo"
  ingress {
    protocol = "icmp"
    from_port = -1
    to_port = -1
    cidr_blocks = ["0.0.0.0/0"]
  }
}

resource "aws_instance" "foo" {
  # eu-west-1
  ami = "ami-f77ac884"
  availability_zone = "eu-west-1a"
  instance_type = "t2.small"
  security_groups = ["${aws_security_group.tf_test_foo.name}"]
}

resource "aws_ssm_document" "foo_document" {
  name    = "test_document_association-%s",
  content = <<DOC
  {
    "schemaVersion": "1.2",
    "description": "Check ip configuration of a Linux instance.",
    "parameters": {

    },
    "runtimeConfig": {
      "aws:runShellScript": {
        "properties": [
          {
            "id": "0.aws:runShellScript",
            "runCommand": ["ifconfig"]
          }
        ]
      }
    }
  }
DOC
}

resource "aws_ssm_association" "foo" {
  name        = "test_document_association-%s",
  instance_id = "${aws_instance.foo.id}"
}