use /opt/stack instead of /opt
diff --git a/files/keystone.conf b/files/keystone.conf
index 85a64a8..cd785a7 100644
--- a/files/keystone.conf
+++ b/files/keystone.conf
@@ -12,7 +12,7 @@
 
 # Log to this file. Make sure you do not set the same log
 # file for both the API and registry servers!
-log_file = /opt/keystone/keystone.log
+log_file = %DEST%/keystone/keystone.log
 
 # List of backends to be configured
 backends = keystone.backends.sqlalchemy