diff --git a/scripts/gnt-backup b/scripts/gnt-backup
index 355359a7b4df5c5e804bd9b96e9cb69646541dfd..ea0cad62fc75d1622635c3d5a6bb6b5e3c76c6cb 100755
--- a/scripts/gnt-backup
+++ b/scripts/gnt-backup
@@ -75,7 +75,8 @@ def ExportInstance(opts, args):
   ignore_remove_failures = opts.ignore_remove_failures
 
   if not opts.node:
-    raise errors.OpPrereqError("Target node must be specified")
+    raise errors.OpPrereqError("Target node must be specified",
+                               errors.ECODE_INVAL)
 
   op = opcodes.OpExportInstance(instance_name=args[0],
                                 target_node=opts.node,