provider/openstack: Fixing boot volume interference

This commit fixes the situation where instances with both a
bootable volume and attached block storage volumes were reporting
an inconsistent state.

builtin/providers/openstack/resource_openstack_compute_instance_v2.go

@@ -1436,12 +1436,25 @@ func getVolumeAttachments(computeClient *gophercloud.ServiceClient, d *schema.Re
 		return err
 	}
 
-	vols := make([]map[string]interface{}, len(attachments))
-	for i, attachment := range attachments {
-		vols[i] = make(map[string]interface{})
-		vols[i]["id"] = attachment.ID
-		vols[i]["volume_id"] = attachment.VolumeID
-		vols[i]["device"] = attachment.Device
+	var vols []map[string]interface{}
+	for _, attachment := range attachments {
+		// ignore the volume if it is attached as a root device
+		rootDevFound := false
+		for _, rootDev := range []string{"/dev/vda", "/dev/xda", "/dev/sda", "/dev/xvda"} {
+			if attachment.Device == rootDev {
+				rootDevFound = true
+			}
+		}
+
+		if rootDevFound {
+			continue
+		}
+
+		vol := make(map[string]interface{})
+		vol["id"] = attachment.ID
+		vol["volume_id"] = attachment.VolumeID
+		vol["device"] = attachment.Device
+		vols = append(vols, vol)
 	}
 	log.Printf("[INFO] Volume attachments: %v", vols)
 	d.Set("volume", vols)

builtin/providers/openstack/resource_openstack_compute_instance_v2_test.go

@@ -388,6 +388,47 @@ func TestAccComputeV2Instance_bootFromVolumeImage(t *testing.T) {
 	})
 }
 
+func TestAccComputeV2Instance_bootFromVolumeImageWithAttachedVolume(t *testing.T) {
+	var instance servers.Server
+	var testAccComputeV2Instance_bootFromVolumeImageWithAttachedVolume = fmt.Sprintf(`
+		resource "openstack_blockstorage_volume_v1" "volume_1" {
+  		name = "volume_1"
+  		size = 1
+		}
+
+		resource "openstack_compute_instance_v2" "instance_1" {
+			name = "instance_1"
+			security_groups = ["default"]
+			block_device {
+				uuid = "%s"
+				source_type = "image"
+				volume_size = 2
+				boot_index = 0
+				destination_type = "volume"
+				delete_on_termination = true
+			}
+
+			volume {
+				volume_id = "${openstack_blockstorage_volume_v1.volume_1.id}"
+			}
+		}`,
+		os.Getenv("OS_IMAGE_ID"))
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckComputeV2InstanceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccComputeV2Instance_bootFromVolumeImageWithAttachedVolume,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.instance_1", &instance),
+				),
+			},
+		},
+	})
+}
+
 func TestAccComputeV2Instance_bootFromVolumeVolume(t *testing.T) {
 	var instance servers.Server
 	var testAccComputeV2Instance_bootFromVolumeVolume = fmt.Sprintf(`