diff --git a/devstack-vm-gate.sh b/devstack-vm-gate.sh
index 377b2208..399df860 100755
--- a/devstack-vm-gate.sh
+++ b/devstack-vm-gate.sh
@@ -42,6 +42,7 @@ SERVICE_PASSWORD=secret
 SERVICE_TOKEN=111222333444
 SWIFT_HASH=1234123412341234
 ROOTSLEEP=0
+ERROR_ON_CLONE=True
 ENABLED_SERVICES=$ENABLED_SERVICES
 SKIP_EXERCISES=boot_from_volume,client-env,swift
 SERVICE_HOST=127.0.0.1