Use following command to setup VPN on Ubuntu or Debian:
$ sudo apt-get update
$ wget https://git.io/vpnsetup -O vpnsetup.sh && sudo sh vpnsetup.sh
Use following command to setup VPN on Centos:
$ sudo yum update
$ wget https://git.io/vpnsetup-centos -O vpnsetup.sh && sudo sh vpnsetup.sh
When the installation is completed, the vpn connect information will appear on the screen.