diff --git a/manifests/firewall/iptables.pp b/manifests/firewall/iptables.pp
index 42597ad..8c10c6a 100644
--- a/manifests/firewall/iptables.pp
+++ b/manifests/firewall/iptables.pp
@@ -28,7 +28,7 @@ class cd_nrpe::firewall::iptables (
 
     firewall { "${ne_fw_order_no}${ne_nrpe_port} port ${ne_nrpe_port}":
       source  => $nagios_server,
-      proto   => 'all',
+      proto   => ['tcp','udp'],
       dport   => $ne_nrpe_port,
       jump    => 'accept',
     }