This guide will assist you through the ZyWALL L2TP wizard setup.
Login to the ZyWALL's web configuration setup and go to the Configuration menu. In the configuration menu there is an option for "Quick Setup". Click on this "Quick Setup" option to launch the wizard.
Select the VPN Setup option to run the VPN wizard.
You will be presented with three VPN setup options, select "VPN Settings for L2TP…" and click the Next button.
For the Phase 1 Setting select the WAN (internet) connection you wish to use to establish the tunnel with. Create a Pre-Shared key and click on the Next button to continue the wizard setup.
Create a range of IP addresses to be assigned to L2TP clients. The IP range must be different than the IP schemes being used by the LAN1, LAN2, DMZ, etc., to avoid routing issues. You may also want to assign some DNS server settings if you will be allowing internet traffic to go through the L2TP tunnel. By default, with L2TP all traffic will be sent by the client through the tunnel, if you do not have DNS servers configured for the L2TP clients they will not be able to resolve domain names to get online. Click the Next button to proceed.
The screen will show a summary of the IPSec setup portion of the L2TP tunnel. Click the Save button to continue.
The final screen will show a summary of the L2TP setup portion of the tunnel. Click Close to end the wizard setup and apply all changes.