diff --git a/root/defaults/smoke-conf/Probes b/root/defaults/smoke-conf/Probes
index 053b7a8..c89ea1d 100644
--- a/root/defaults/smoke-conf/Probes
+++ b/root/defaults/smoke-conf/Probes
@@ -2,6 +2,7 @@
 
 + FPing
 binary = /usr/sbin/fping
+protocol = 4
 
 + FPing6
 binary = /usr/sbin/fping