diff --git a/lamp-trusty64/Vagrantfile b/lamp-trusty64/Vagrantfile
index 509c430..069f72f 100644
--- a/lamp-trusty64/Vagrantfile
+++ b/lamp-trusty64/Vagrantfile
@@ -24,7 +24,7 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
 
   # Create a private network, which allows host-only access to the machine
   # using a specific IP.
-  config.vm.network "private_network", ip: "192.168.33.10"
+  config.vm.network "private_network", ip: "192.168.33.10", netmask: "255.255.255.0"
 
   # Create a public network, which generally matched to bridged network.
   # Bridged networks make the machine appear as another physical device on