diff --git a/neutron/db/l3_dvr_db.py b/neutron/db/l3_dvr_db.py
index 337253bfd72..4a278e5b5a5 100644
--- a/neutron/db/l3_dvr_db.py
+++ b/neutron/db/l3_dvr_db.py
@@ -289,9 +289,10 @@ class L3_NAT_with_dvr_db_mixin(l3_db.L3_NAT_db_mixin,
             if subnet['ip_version'] == 6:
                 # Add new prefix to an existing ipv6 csnat port with the
                 # same network id if one exists
-                cs_port = self._find_router_port_by_network_and_device_owner(
-                    router, subnet['network_id'],
-                    const.DEVICE_OWNER_ROUTER_SNAT)
+                cs_port = (
+                    self._find_v6_router_port_by_network_and_device_owner(
+                        router, subnet['network_id'],
+                        const.DEVICE_OWNER_ROUTER_SNAT))
                 if cs_port:
                     fixed_ips = list(cs_port['port']['fixed_ips'])
                     fixed_ips.append(fixed_ip)
@@ -329,7 +330,7 @@ class L3_NAT_with_dvr_db_mixin(l3_db.L3_NAT_db_mixin,
         return super(L3_NAT_with_dvr_db_mixin,
                      self)._port_has_ipv6_address(port)
 
-    def _find_router_port_by_network_and_device_owner(
+    def _find_v6_router_port_by_network_and_device_owner(
         self, router, net_id, device_owner):
         for port in router.attached_ports:
             p = port['port']
@@ -351,7 +352,7 @@ class L3_NAT_with_dvr_db_mixin(l3_db.L3_NAT_db_mixin,
         if router.gw_port:
             # If router has a gateway port, check if it has IPV6 subnet
             cs_port = (
-                self._find_router_port_by_network_and_device_owner(
+                self._find_v6_router_port_by_network_and_device_owner(
                     router, network_id, const.DEVICE_OWNER_ROUTER_SNAT))
             if cs_port:
                 fixed_ips = (