Ignore IOPS on non io1 AWS devices

- Already ignoring IOPS on ebs attached non-io1 devices; extended to root_block_device
- Added warning captured from hashicorp#4146 / [../blob/master/builtin/providers/aws/resource_aws_ebs_volume.go#L104](resource_aws_ebs_volume.go#L104)
- Added test when setting IOPS to 330 (11GiB * 30 = 330) on GP2 root device results in AWS reported 100 IOPS (successfully ignored input)

builtin/providers/aws/resource_aws_instance.go

@@ -931,8 +931,16 @@ func readBlockDeviceMappingsFromConfig(
  ebs.VolumeType = aws.String(v)
  }
 
- if v, ok := bd["iops"].(int); ok && v > 0 {
+ if v, ok := bd["iops"].(int); ok && v > 0 && *ebs.VolumeType == "io1" {
+ // Only set the iops attribute if the volume type is io1. Setting otherwise
+ // can trigger a refresh/plan loop based on the computed value that is given
+ // from AWS, and prevent us from specifying 0 as a valid iops.
+ // See https://github.com/hashicorp/terraform/pull/4146
+ // See https://github.com/hashicorp/terraform/issues/7765
  ebs.Iops = aws.Int64(int64(v))
+ } else if v, ok := bd["iops"].(int); ok && v > 0 && *ebs.VolumeType != "io1" {
+ // Message user about incompatibility
+ log.Printf("[WARN] IOPs is only valid for storate type io1 for EBS Volumes")
  }
 
  if dn, err := fetchRootDeviceName(d.Get("ami").(string), conn); err == nil {

builtin/providers/aws/resource_aws_instance_test.go

@@ -105,6 +105,56 @@ func TestAccAWSInstance_basic(t *testing.T) {
  })
 }
 
+func TestAccAWSInstance_GP2IopsDevice(t *testing.T) {
+ var v ec2.Instance
+
+ testCheck := func() resource.TestCheckFunc {
+ return func(*terraform.State) error {
+
+ // Map out the block devices by name, which should be unique.
+ blockDevices := make(map[string]*ec2.InstanceBlockDeviceMapping)
+ for _, blockDevice := range v.BlockDeviceMappings {
+ blockDevices[*blockDevice.DeviceName] = blockDevice
+ }
+
+ // Check if the root block device exists.
+ if _, ok := blockDevices["/dev/sda1"]; !ok {
+ return fmt.Errorf("block device doesn't exist: /dev/sda1")
+ }
+
+ return nil
+ }
+ }
+
+ resource.Test(t, resource.TestCase{
+ PreCheck: func() { testAccPreCheck(t) },
+ IDRefreshName: "aws_instance.foo",
+ IDRefreshIgnore: []string{
+ "ephemeral_block_device", "user_data", "security_groups", "vpc_security_groups"},
+ Providers: testAccProviders,
+ CheckDestroy: testAccCheckInstanceDestroy,
+ Steps: []resource.TestStep{
+ resource.TestStep{
+ Config: testAccInstanceGP2IopsDevice,
+ //Config: testAccInstanceConfigBlockDevices,
+ Check: resource.ComposeTestCheckFunc(
+ testAccCheckInstanceExists(
+ "aws_instance.foo", &v),
+ resource.TestCheckResourceAttr(
+ "aws_instance.foo", "root_block_device.#", "1"),
+ resource.TestCheckResourceAttr(
+ "aws_instance.foo", "root_block_device.0.volume_size", "11"),
+ resource.TestCheckResourceAttr(
+ "aws_instance.foo", "root_block_device.0.volume_type", "gp2"),
+ resource.TestCheckResourceAttr(
+ "aws_instance.foo", "root_block_device.0.iops", "100"),
+ testCheck(),
+ ),
+ },
+ },
+ })
+}
+
 func TestAccAWSInstance_blockDevices(t *testing.T) {
  var v ec2.Instance
 
@@ -738,6 +788,24 @@ resource "aws_instance" "foo" {
 }
 `
 
+const testAccInstanceGP2IopsDevice = `
+resource "aws_instance" "foo" {
+ # us-west-2
+ ami = "ami-55a7ea65"
+
+ # In order to attach an encrypted volume to an instance you need to have an
+ # m3.medium or larger. See "Supported Instance Types" in:
+ # http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSEncryption.html
+ instance_type = "m3.medium"
+
+ root_block_device {
+ volume_type = "gp2"
+ volume_size = 11
+ iops = 330
+ }
+}
+`
+
 const testAccInstanceConfigBlockDevices = `
 resource "aws_instance" "foo" {
  # us-west-2