diff --git a/Makefile b/Makefile
index db88035..04710cc 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@ require-%:
 	fi
 
 server: require-K8S_NODE
-	cat k8s-iperf.yaml | sed -s "s/{NODE}/$(K8S_NODE)/g" | kubectl apply -f -
+	sed "s/{NODE}/$(K8S_NODE)/g" k8s-iperf.yaml | kubectl apply -f -
 
 client: require-K8S_NODE
 	@if [[ "$$(kubectl get pod -l app=iperf-server 2> /dev/null)" == "" ]]; then \
@@ -18,4 +18,4 @@ client: require-K8S_NODE
 clean:
 	@if [[ "$$(kubectl get pod -l app=iperf-server)" != "" || "$$(kubectl get pod -l app=iperf-client)" != "" ]]; then \
 		kubectl delete --cascade -f k8s-iperf.yaml; \
-	fi
\ No newline at end of file
+	fi
diff --git a/k8s-iperf b/k8s-iperf
index c3daee7..df7004a 100755
--- a/k8s-iperf
+++ b/k8s-iperf
@@ -5,7 +5,7 @@ function print_usage() {
     >&2 echo "Usage: `basename $0` <Server Node> [iperf options]"
 }
 
-if [[ $# < 1 ]]; then 
+if [[ $# < 1 ]]; then
     print_usage
     exit 1
 fi
@@ -17,9 +17,9 @@ if [[ ! $(kubectl get node -o name | grep "node/${SERVER_NODE}") ]]; then
     exit 1
 fi
 
-echo "[Start] iperf server"
+echo "[Start] iperf server on ${SERVER_NODE}"
 if [[ ! $(kubectl get pods -l app=iperf-server 2> /dev/null) ]]; then
-    cat ${DIR}/k8s-iperf.yaml | sed -s "s/{NODE}/${SERVER_NODE}/g" | kubectl apply -f -
+    sed "s/{NODE}/${SERVER_NODE}/g" "${DIR}/k8s-iperf.yaml" | kubectl apply -f -
 elif [[ $(kubectl get pod -l app=iperf-server -o jsonpath='{.items[0].metadata.labels.node}') != "${SERVER_NODE}" ]]; then
     >&2 echo "[Error] Another server had been launched."
     >&2 echo "$(kubectl get pods -l app=iperf-server -o wide)"
@@ -32,7 +32,7 @@ until $(kubectl get pods -l app=iperf-server -o jsonpath='{.items[0].status.cont
 done
 echo
 
-echo "[Start] iperf clients" 
+echo "[Start] iperf clients"
 CLIENTS=$(kubectl get pods -l app=iperf-client -o name | cut -d'/' -f2)
 for POD in ${CLIENTS}; do
     until $(kubectl get pod ${POD} -o jsonpath='{.status.containerStatuses[0].ready}'); do
@@ -53,7 +53,7 @@ done
 printf " done\n"
 
 echo
-kubectl logs -l app=iperf-server 
+kubectl logs -l app=iperf-server
 echo
 
 echo "[Cleanup]"