diff --git a/scripts/switch.sh b/scripts/switch.sh
new file mode 100755
index 0000000..648b5cd
--- /dev/null
+++ b/scripts/switch.sh
@@ -0,0 +1,26 @@
+#! /bin/bash
+controller=`hostname`
+switches=`ifconfig -a | grep sw |grep -v eth | awk '{print $1}'`
+
+function host2ip (){
+   ip=`grep $1 /etc/hosts |grep -v "ip6"|  awk '{print $1}'`
+   echo $ip
+}
+
+url=""
+for c in $controller; do
+  url="$url tcp:`host2ip $c`:6633"
+done
+
+for s in $switches; do
+    dpid=`sudo ovs-ofctl  show  $s |grep dpid | awk '{split($4,x,":"); print x[2]}'`
+    if [  "x$dpid" == "x$1" ]; then
+        if [ x$2 == "xup" ]; then
+           sudo ovs-vsctl set-controller $s $url 
+        elif [ x$2 == "xdown" ]; then
+           sudo ovs-vsctl set-controller $s
+        else
+           sudo ovs-vsctl get-controller $s
+        fi
+    fi
+done