Issues installing flow rules

[haazy]

I am trying to install flow rules and I ran this command
sudo ./l2_switch.sh

And I got the error below.

#! /bin/sh -ve

Please make sure that you update the path to the current OVS directory.

DIR=~/ovs/utilities
#DIR=/vagrant/examples/l2_switch
$DIR/ovs-ofctl --protocols=OpenFlow15 del-flows br0
ovs-ofctl: /usr/local/var/run/openvswitch/br0.mgmt: failed to open socket (Connection refused)

Can anyone help me ?