diff --git a/ironic/drivers/modules/deploy_utils.py b/ironic/drivers/modules/deploy_utils.py
index ce7da1971a..4cf11d1a6a 100644
--- a/ironic/drivers/modules/deploy_utils.py
+++ b/ironic/drivers/modules/deploy_utils.py
@@ -401,12 +401,13 @@ def deploy_disk_image(address, port, iqn, lun,
     with _iscsi_setup_and_handle_errors(address, port, iqn,
                                         lun) as dev:
         disk_utils.populate_image(image_path, dev)
-        disk_identifier = disk_utils.get_disk_identifier(dev)
 
         if configdrive:
             disk_utils.create_config_drive_partition(node_uuid, dev,
                                                      configdrive)
 
+        disk_identifier = disk_utils.get_disk_identifier(dev)
+
     return {'disk identifier': disk_identifier}
 
 
diff --git a/releasenotes/notes/fix-disk-identifier-overwrite-42b33a5a0f7742d8.yaml b/releasenotes/notes/fix-disk-identifier-overwrite-42b33a5a0f7742d8.yaml
new file mode 100644
index 0000000000..6404bc15ea
--- /dev/null
+++ b/releasenotes/notes/fix-disk-identifier-overwrite-42b33a5a0f7742d8.yaml
@@ -0,0 +1,5 @@
+---
+fixes:
+  - Fix handling of whole disk images with 0x00000000 disk identifier.
+    Instances failed to boot as the identifier in boot config was overwritten
+    during config drive creation. See https://bugs.launchpad.net/ironic/+bug/1685093