diff --git a/opencontrail/files/2.2/contrail-vrouter-agent.conf b/opencontrail/files/2.2/contrail-vrouter-agent.conf
index 6a7078c..68d31f5 100644
--- a/opencontrail/files/2.2/contrail-vrouter-agent.conf
+++ b/opencontrail/files/2.2/contrail-vrouter-agent.conf
@@ -64,6 +64,9 @@
 # DHCP relay mode (true or false) to determine if a DHCP request in fabric
 # interface with an unconfigured IP should be relayed or not
 # dhcp_relay_mode=
+{%- if tor.enabled %}
+agent_mode = tsn
+{%- endif %}
 
 [DISCOVERY]
 # If COLLECTOR and/or CONTROL-NODE and/or DNS is not specified this section is