more complete diagnostic playbook
diff --git a/inventory/single-localhost b/inventory/single-localhost
index 5b70063..7f86038 100644
--- a/inventory/single-localhost
+++ b/inventory/single-localhost
@@ -1,5 +1,5 @@
 [all:vars]
-ansible_ssh_user=ubuntu
+ansible_ssh_user=replaceme
 
 [head]
 localhost
@@ -8,5 +8,5 @@
 localhost
 
 [compute]
-nova-compute-1
+nova-compute-1 ansible_ssh_user=ubuntu