Adding a double tagged host in trellis.py
Updating the vagrant file to upgrande linux kernel to 4.15
and install ovs 2.9.2

Change-Id: Ic14f3d79fe65bca07960070f2b6e6151b33e5b7b
diff --git a/trellis/Vagrantfile b/trellis/Vagrantfile
index a46672e..0c04e17 100644
--- a/trellis/Vagrantfile
+++ b/trellis/Vagrantfile
@@ -1,9 +1,21 @@
 # -*- mode: ruby -*-
 # vi: set ft=ruby :
 
+required_plugins = %w(vagrant-reload vagrant-vbguest)
+
+plugins_to_install = required_plugins.select { |plugin| not Vagrant.has_plugin? plugin }
+if not plugins_to_install.empty?
+  puts "Installing plugins: #{plugins_to_install.join(' ')}"
+  if system "vagrant plugin install #{plugins_to_install.join(' ')}"
+    exec "vagrant #{ARGV.join(' ')}"
+  else
+    abort "Installation of one or more plugins has failed. Aborting."
+  end
+end
+
 Vagrant.configure("2") do |config|
   config.vm.box = "ubuntu/xenial64"
-  config.vm.box_version = "20171221.0.0"
+  config.vm.box_version = "20180717.0.0"
   config.vm.hostname = 'trellis-example'
   config.ssh.forward_agent = true
   config.ssh.forward_x11 = true
@@ -32,7 +44,32 @@
     git clone https://gerrit.onosproject.org/routing
 
     sudo ldconfig
-    SHELL
+
+    mkdir 4.15 && cd 4.15
+    wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-headers-4.15.0-041500_4.15.0-041500.201802011154_all.deb
+    wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-headers-4.15.0-041500-generic_4.15.0-041500.201802011154_amd64.deb
+    wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-image-4.15.0-041500-generic_4.15.0-041500.201802011154_amd64.deb
+    sudo dpkg -i *.deb
+  SHELL
+
+  config.vm.provision :reload
+
+  config.vm.provision "shell", privileged: true, inline: <<-SHELL
+    /etc/init.d/openvswitch-switch stop
+    cd /tmp
+    wget http://openvswitch.org/releases/openvswitch-2.9.2.tar.gz
+    tar zxvf openvswitch-2.9.2.tar.gz
+    cd openvswitch-2.9.2
+    ./configure --prefix=/usr --with-linux=/lib/modules/`uname -r`/build
+    make
+    make install
+    make modules_install
+    rmmod openvswitch
+    depmod -a
+    /etc/init.d/openvswitch-switch start
+    rm -rf /tmp/openvswitch-2.9.2*
+    ovs-vsctl set Open_vSwitch . other_config:vlan-limit=2
+  SHELL
 
   config.vm.provider :virtualbox do |v|
       v.customize ["modifyvm", :id, "--cpus", 2]