diff -uNr cloud-init-0.7.5__orig/cloudinit/sources/DataSourceOpenNebula.py cloud-init-0.7.5/cloudinit/sources/DataSourceOpenNebula.py
--- cloud-init-0.7.5__orig/cloudinit/sources/DataSourceOpenNebula.py	2014-08-29 11:01:19.817660822 +0100
+++ cloud-init-0.7.5/cloudinit/sources/DataSourceOpenNebula.py	2014-08-29 11:02:19.641660786 +0100
@@ -288,8 +288,7 @@
 
 
 def switch_user_cmd(user):
-    return ['sudo', '-u', user]
-
+    return ['runuser', '-u', user, '--']
 
 def parse_shell_config(content, keylist=None, bash=None, asuser=None,
                        switch_user_cb=None):