diff --git a/devstack/plugin.sh b/devstack/plugin.sh
index ac6c56332..595746780 100644
--- a/devstack/plugin.sh
+++ b/devstack/plugin.sh
@@ -7,6 +7,7 @@ function neutron_lbaas_install {
 
 function neutron_agent_lbaas_install_agent_packages {
     if is_ubuntu; then
+        sudo apt-get -y install software-properties-common
         sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu trusty-backports main restricted universe multiverse" -y
         sudo apt-get update
         sudo apt-get install haproxy -t trusty-backports