VPN practical tips

Virtual Private Networking (VPN) concepts

Overview

This Howto gives practical examples regarding using VPN and making connections to remote servers and workstations.

Please refer to seperate Howtos for configuration of the VPN client on Windows 2000, XP and other workstations

http://www.domain-logic.com/support/secure_tunnel_w2k.htm

http://www.domain-logic.com/support/secure_tunnel_XP.htm

Background information

VPN uses port 1723 and protocol 47.

In server & gateway mode your modem should be configured in bridged mode and automatically forwards all traffic to the server.

In server only mode, your router must be configured to forward port 1723 to your server and must provide full support for protocol 47. Note that protocol 47 (GRE) is not a port and therefore you cannot forward it. Not all routers support this protocol so VPN is not always possible in this network arrangement.

You cannot establish a VPN passthrough connection through an SME server to a local machine due to problems with the sme server supporting the passthrough of protocol 47 (GRE).

VPN connections to workstations will run very slowly. It is not advisable to run programs across VPN connections, even with fast broadband Internet speeds. This applies to scenarios where a VPN connection is established to a sme server, and then a connection is made to a workstation on the remote network.

Check that the VPN user(s) in server-manager User panel are allowed VPN access

Check that the "Number of pptp clients" in the "Remote access" panel in server manager, is set to more than zero

Check that the connection is set to "Negotiate multi-link connections" in the Windows VPN client setup

Check that the VPN connection/service is allowed access through a personal firewall on Windows workstations

Please read the sections of the SME server manual that relate to VPN

For further information please also search the forums and bugzilla for numerous reports of localised and other issues using VPN

Establishing connections & drive mapping

	Note:
	The following presupposes that if VPN'ing from behind another sme server, then the IP number and name of the local sme server & the remote sme server are different.

After establishing a VPN connection with the sme server, users then need to connect to shares

to map a ibay do

net use N: \\serverIP\ibayname

net use N: \\servername\ibayname

to see all server shares do

\\serverIP

\\servername

to connect to a workstation C: or D: drive (that has been shared in Windows) do

\\workstationname

\\workstationIP

net use W: \\workstationIP\c

IPSec network to network VPN

For establishing a permanent VPN connection between networks see http://wiki.contribs.org/Ipsec

Remote Desktop Protocol (RDP)

A good alternative to access workstations behind a SME server on a remote network, is Remote Desktop Protocol (RDP). It uses encrypted connections, is fast and flexible.

In use, forward a chosen port (say 2345), either in the port forwarding server manager panel (sme in server gateway mode) or in your router (sme in server only mode), to port 3389 on a workstation, which will allow direct RDP access to that workstation using a URL like http://yourdomain:2345

See

http://en.wikipedia.org/wiki/Remote_Desktop_Protocol

http://msdn2.microsoft.com/en-us/library/aa383015.aspx

http://support.microsoft.com/kb/186607

Reference links

http://forums.contribs.org/index.php?topic=40314.0

https://secure.logmein.com/home.asp?lang=en

http://wiki.contribs.org/Ipsec