diff --git a/firewall.tf b/firewall.tf
index 3e896c85e8c3574454c8e6362090fed26543a964..b0b9c770cbf566ba75ab1f73248da37ac55b63a0 100644
--- a/firewall.tf
+++ b/firewall.tf
@@ -50,6 +50,6 @@ resource "openstack_networking_secgroup_rule_v2" "secgroup_rule_other6" {
 resource "openstack_networking_secgroup_rule_v2" "secgroup_rule_floatip" {
 	direction = "ingress"
 	ethertype = "IPv4"
-	remote_ip_prefix = openstack_networking_floatingip_v2.floatip_1.address
+	remote_ip_prefix = "${openstack_networking_floatingip_v2.floatip_1.address}/32"
 	security_group_id = openstack_networking_secgroup_v2.secgroup.id
 }