diff --git a/backend/kolla/prepare.sh b/backend/kolla/prepare.sh
index 4e623209..8d3056ea 100755
--- a/backend/kolla/prepare.sh
+++ b/backend/kolla/prepare.sh
@@ -54,5 +54,5 @@ docker load < $prepare_dir/registry-server.tar
 
 #enlarge the TCP source port range to deal with functest thousands requests
 sudo sysctl net.ipv4.ip_local_port_range="5000 65000"
-echo -e "net.ipv4.ip_local_port_range='5000 65000'" >> /etc/sysctl.conf
+echo -e "net.ipv4.ip_local_port_range= 5000 65000" >> /etc/sysctl.conf