diff --git a/etc/metering_agent.ini b/etc/metering_agent.ini
index e6ab5220965..88826ce79f0 100644
--- a/etc/metering_agent.ini
+++ b/etc/metering_agent.ini
@@ -2,6 +2,9 @@
 # Show debugging output in log (sets DEBUG log level output)
 # debug = True
 
+# Default driver:
+# driver = neutron.services.metering.drivers.noop.noop_driver.NoopMeteringDriver
+# Example of non-default driver
 # driver = neutron.services.metering.drivers.iptables.iptables_driver.IptablesMeteringDriver
 
 # Interval between two metering measures