IPsec VPN Server Auto Setup Scripts  

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Set up your own IPsec VPN server in just a few minutes, with both IPsec/L2TP and Cisco IPsec on Ubuntu, Debian and CentOS. All you need to do is provide your own VPN credentials, and let the scripts handle the rest.

We will use Libreswan as the IPsec server, and xl2tpd as the L2TP provider.

» Related tutorial: IPsec VPN Server Auto Setup with Libreswan

Table of Contents

• Features
• Requirements
• Installation
  • Ubuntu & Debian
  • CentOS & RHEL
• Next Steps
• Important Notes
• Upgrade Libreswan
• Bugs & Questions
• Uninstallation
• See Also
• Author
• License

Features

• New: The faster IPsec/XAuth ("Cisco IPsec") mode is supported
• New: A pre-built Docker image of the VPN server is now available
• Fully automated IPsec VPN server setup, no user input needed
• Encapsulates all VPN traffic in UDP - does not need ESP protocol
• Can be directly used as "user-data" for a new Amazon EC2 instance
• Automatically determines public IP and private IP of server
• Includes basic IPTables rules and sysctl.conf settings
• Tested with Ubuntu 16.04/14.04/12.04, Debian 8 and CentOS 6 & 7

Requirements

A newly created Amazon EC2 instance, using these AMIs: (See instructions)

• Ubuntu 16.04 (Xenial), 14.04 (Trusty) or 12.04 (Precise)
• Debian 8 (Jessie) EC2 Images
• CentOS 7 (x86_64) with Updates
• CentOS 6 (x86_64) with Updates

-OR-

A dedicated server or Virtual Private Server (VPS), freshly installed with one of the above OS. In addition, Debian 7 (Wheezy) can also be used with this workaround. OpenVZ VPS is not supported, users could instead try OpenVPN.

This also includes Linux VMs in public clouds such as Google Compute Engine, Amazon EC2, Microsoft Azure, IBM SoftLayer, VMware vCloud Air, Rackspace, DigitalOcean, Vultr and Linode.

» I want to run my own VPN but don't have a server for that

⚠️ DO NOT run these scripts on your PC or Mac! They should only be used on a server!

Installation

Ubuntu & Debian

First, update your system with apt-get update && apt-get dist-upgrade and reboot. This is optional, but recommended.

To install the VPN, please choose one of the following options:

Option 1: Have the script generate random VPN credentials for you (will be displayed when finished):

wget https://git.io/vpnsetup -O vpnsetup.sh && sudo sh vpnsetup.sh

Option 2: Edit the script and provide your own VPN credentials:

wget https://git.io/vpnsetup -O vpnsetup.sh
nano -w vpnsetup.sh
[Replace with your own values: YOUR_IPSEC_PSK, YOUR_USERNAME and YOUR_PASSWORD]
sudo sh vpnsetup.sh

Option 3: Define your VPN credentials as environment variables:

# All values MUST be placed inside 'single quotes'
# DO NOT use these characters within values:  \ " '
wget https://git.io/vpnsetup -O vpnsetup.sh && sudo \
VPN_IPSEC_PSK='your_ipsec_pre_shared_key' \
VPN_USER='your_vpn_username' \
VPN_PASSWORD='your_vpn_password' sh vpnsetup.sh

For installation on DigitalOcean, check out this step-by-step guide by Tony Tran.

Note: If unable to download via wget, you may also open vpnsetup.sh (or vpnsetup_centos.sh) and click the Raw button. Press Ctrl-A to select all, Ctrl-C to copy, then paste into your favorite editor.

CentOS & RHEL

First, update your system with yum update and reboot. This is optional, but recommended.

Follow the same steps as above, but replace https://git.io/vpnsetup with https://git.io/vpnsetup-centos.

Next Steps

Get your computer or device to use the VPN. Please refer to:

Configure IPsec/L2TP VPN Clients
Configure IPsec/XAuth ("Cisco IPsec") VPN Clients

Enjoy your very own VPN! ✨🎉🚀✨

Important Notes

For Windows users, this one-time registry change is required if the VPN server and/or client is behind NAT (e.g. home router). If you get an error when trying to connect, see Troubleshooting.

Android 6 (Marshmallow) users: Please see notes in Configure IPsec/L2TP VPN Clients.

If you wish to add, edit or remove VPN user accounts, refer to Manage VPN Users.

Clients are set to use Google Public DNS when the VPN is active. If another DNS provider is preferred, replace 8.8.8.8 and 8.8.4.4 in both /etc/ppp/options.xl2tpd and /etc/ipsec.conf. Then reboot your server.

For servers with an external firewall (e.g. EC2/GCE), open UDP ports 500 & 4500, and TCP port 22 (for SSH).

To open additional ports on the server, edit /etc/iptables.rules and/or /etc/iptables/rules.v4 (Ubuntu/Debian), or /etc/sysconfig/iptables (CentOS). Then reboot your server.

When connecting via IPsec/L2TP, the VPN server has IP 192.168.42.1 within the VPN subnet 192.168.42.0/24.

The scripts will backup existing config files before making changes, with .old-date-time suffix.

Upgrade Libreswan

The additional scripts vpnupgrade.sh and vpnupgrade_centos.sh can be used to upgrade Libreswan (website | mailing list). Edit the swan_ver variable as necessary. Check installed version: ipsec --version

Bugs & Questions

• Got a question? Please first search other people's comments in this Gist and on my blog.
• Ask Libreswan (IPsec) related questions on the mailing list, or read these articles: [1] [2] [3] [4] [5].
• If you found a reproducible bug, open a GitHub Issue to submit a bug report.

Uninstallation

Please refer to Uninstall the VPN.

See Also

• IPsec VPN Server on Docker
• Streisand
• SoftEther VPN
• ShadowsocksR
• OpenVPN Install
• VPN Deploy Playbook
• Insta VPN
• One Key IKEv2 VPN

Author

Lin Song (linsongui@gmail.com)

• Final year U.S. PhD candidate, majoring in Electrical and Computer Engineering (ECE)
• Actively seeking opportunities in areas such as Software or Systems Engineering
• Contact me on LinkedIn: https://www.linkedin.com/in/linsongui

Thanks to all contributors to this project!

License

Copyright (C) 2014-2016 Lin Song   
Based on the work of Thomas Sarlandie (Copyright 2012)

This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License
Attribution required: please include my name in any derivative and let me know how you have improved it!