diff --git a/quantum/agent/dhcp_agent.py b/quantum/agent/dhcp_agent.py
index ad22e03049..70a547a51e 100644
--- a/quantum/agent/dhcp_agent.py
+++ b/quantum/agent/dhcp_agent.py
@@ -325,7 +325,7 @@ class DhcpAgent(manager.Manager):
         pm = external_process.ProcessManager(
             self.conf,
             network.id,
-            self.conf.root_helper,
+            self.root_helper,
             self._ns_name(network))
         pm.enable(callback)
 
@@ -333,7 +333,7 @@ class DhcpAgent(manager.Manager):
         pm = external_process.ProcessManager(
             self.conf,
             network.id,
-            self.conf.root_helper,
+            self.root_helper,
             self._ns_name(network))
         pm.disable()