Download from https://www.virtualbox.org/wiki/Downloads or for Ubuntu distributions install from package.
sudo apt-get install virtualbox
Download from http://www.vagrantup.com/downloads.html or for Ubuntu distributions install from packages.
sudo apt-get install vagrant
git clone https://github.com/Redexperts/vagrant-ubuntu-server-14.04.git
cd vagrant-ubuntu-server-14.04
rm ./.git -Rf
vagrant up
This will take a moment to download vagrant box from server and install required packages. When server is ready you can login by ssh:
vagrant ssh
To stop and save virtual machine status close ssh connection
exit
vagrant suspend