diff --git a/unbound/unbound.sh b/unbound/unbound.sh
index b6c4e3c..ac8c675 100644
--- a/unbound/unbound.sh
+++ b/unbound/unbound.sh
@@ -351,7 +351,7 @@ EOT
 fi
 
 mkdir -p /opt/unbound/etc/unbound/dev && \
-cp -a /dev/random /dev/urandom /opt/unbound/etc/unbound/dev/
+cp -a /dev/random /dev/urandom /dev/null /opt/unbound/etc/unbound/dev/
 
 mkdir -p -m 700 /opt/unbound/etc/unbound/var && \
 chown _unbound:_unbound /opt/unbound/etc/unbound/var && \