How to build a VPN in Amazon cloud space

The script content is very simple, uses the Yum to install the software, and has made the configuration, but, because I use the Ubuntu image, is apt, therefore needs to make some changes.
Here's my modified script:

#!/bin/bash

# automaticlly Install pptpd on Amazon EC2 Amazon Linux (Ubuntu)
#
#我用的是ubuntu的镜像, the main is to install VPN needs software, set iptables, configure PPP and VPN
#记得添加自定义规则: TCP port 1723, for VPN use
#
#
# Authors:kime (cidy0106#gmail.com)
# version:0.0.1
#
#安装不要软件ppp和pptpd
Apt-get Install PPPTD PPP

#下面是注释掉的, I don't know exactly what the effect is, keep
Sed-i ' s/^logwtmp/#logwtmp/g '/etc/pptpd.conf

#启用转发
Sed-i ' S/^net.ipv4.ip_forward = 0/net.ipv4.ip_forward = 1/g '/etc/sysctl.conf
Sed-i ' s/^net.ipv4.ip_forward=0/net.ipv4.ip_forward=1/g '/etc/sysctl.conf
Sysctl-p

#分配ip, I use 192.168.222 network segment, I can modify, remember the iptable part of the following also need to modify
echo "Localip 192.168.222.1" >>/etc/pptpd.conf
echo "Remoteip 192.168.222.2-100" >>/etc/pptpd.conf

#设置dns, like my VPN server, remember to change it to your own, or it's probably not going to be on the web.
#原文是设置/etc/ppp/options.pptpd file, but I'm not/etc/ppp/pptpd-options, specifically see/etc/pptpd.conf's description

Mydns= ' cat/etc/resolv.conf |grep nameserver | awk ' {print $} '
echo "Ms-dns $mydns" >>/etc/ppp/pptpd-options
echo "Ms-dns 8.8.8.8" >>/etc/ppp/pptpd-options

#iptables--flush postrouting--table NAT
#iptables--flush FORWARD

#下面会生成个默认的密码, change yourself into something easy to remember.
#pass = "Kimeismyhero"

pass= ' OpenSSL rand 8-base64 '
If ["!="]
Then pass=$1
Fi

echo "VPN pptpd ${pass} *" >>/etc/ppp/chap-secrets

Iptables-t nat-a postrouting-s 192.168.222.0/24-j SNAT--to-source ' ifconfig | grep ' inet addr: ' | Grep-v ' 127.0.0.1 ' | Cut-d:-f2 | awk ' nr==1 {print $} '
Iptables-a forward-p TCP--syn-s 192.168.222.0/24-j TCPMSS--SET-MSS 1356

#service iptables Save
#chkconfig iptables on
#chkconfig pptpd on
#service iptables Start

Service pptpd Restart

ECHO-E "VPN service is installed, your VPN username are \033[1mvpn\033[0m, VPN password is \033[1m${pass}\033[1m"
Copy the above script to the cloud space, execute it, it should be
The next step is to add a VPN account on the client you need to use VPN (android,window,linux, etc.)