diff --git a/src/freedombone-utils-firewall b/src/freedombone-utils-firewall
index 3c5a94f9..d661c008 100755
--- a/src/freedombone-utils-firewall
+++ b/src/freedombone-utils-firewall
@@ -53,12 +53,12 @@ function block_firefox_telemetry {
     # to be on the safe side
     # Within firefox source code see submit_telemetry_data.py
 
-    if ! grep 'telemetry.mozilla' /etc/hosts; then
+    if ! grep -q 'telemetry.mozilla' /etc/hosts; then
 	echo '127.0.0.1  telemetry.mozilla.org' >> /etc/hosts
 	echo '127.0.0.1  incoming.telemetry.mozilla.org' >> /etc/hosts
     fi
         
-    if grep "$FIREFOX_TELEMETRY_IP" /etc/firewall.conf; then
+    if grep -q "$FIREFOX_TELEMETRY_IP" /etc/firewall.conf; then
         return
     fi