Solved

Remote Desktop and VPN

Posted on 2009-07-16
7
529 Views
Last Modified: 2012-06-27
I can connect to our VPN successfully but I can not then remote desktop anywhere. The VPN connection is done using L2TP on smoothwall and I connect to 192.168.1.171 on the remote network. I then try to connect to 192.168.1.22 but I guess it is looking at my local network rather that the remote one. Any suggestions?
0
Comment
Question by:suroma
  • 4
  • 3
7 Comments
 
LVL 77

Expert Comment

by:Rob Williams
ID: 24870942
Are you saying the remote and local networks use 192.168.1.x?
If so that will not work. With a VPN the remote and local subnets must be different.
0
 

Author Comment

by:suroma
ID: 24871689
The subnet mask of the local network is 255.255.255.0 and the remote one 255.255.255.255??
But surely this would mean most VPN's wouldn't work as they are often between home networks and work networks and most home networks run on 192.168.1.x?
0
 
LVL 77

Expert Comment

by:Rob Williams
ID: 24871765
255.255.255.0 is the subnet mask. I am referring to the network ID or subnet.

If the office to which you are connecting uses a local subnet of 192.168.1.x and the home/client network uses the same the VPN will connect but you will not be able to access resources on the remote network. This is a basic rule of routing and why when setting up a corporate office it is important never to use a common/default subnet. The reason for this is packets are route by their network ID (Subnet to which they belong). If the home network uses 192.168.1.x (assuming subnet mask of 255.255.255.0) and the remote network uses the same, when a packet is destined for the remote network the routing devices see it as a local address and the packet is not forwarded.

The one exception to this is if you enable the "Use default gateway on remote network" option on the VPN client, you can usually access resources on the VPN server, but no other device on the remote network.
0
Efficient way to get backups off site to Azure

This user guide provides instructions on how to deploy and configure both a StoneFly Scale Out NAS Enterprise Cloud Drive virtual machine and Veeam Cloud Connect in the Microsoft Azure Cloud.

 

Author Comment

by:suroma
ID: 24871976
OK I understand so my only option is to change the subnet of the domain here to say 192.168.0.x?
0
 
LVL 77

Accepted Solution

by:
Rob Williams earned 500 total points
ID: 24872050
It is best to change the server site, but this can be a much bigger task. Make sure you plan carefully as to allow for DHCP scopes, printers, statically addressed devices, routers and so on.
If by any chance you are running Microsoft Small Business Server, you MUST use the change server IP wizard in the server management console.

However DO NOT use 192.168.0.x This is even more common that 192.168.1.x and you will have problems with mobile clients staying in hotels and such.
Avoid:
192.168.0.x
192.168.1.x
192.168.2.x
192.168.100.x
192.168.111.x
10.0.0.x
10.10.10.x
172.16.1.x
The above all assume you are using a subnet mask of 255.255.255.0
0
 

Author Closing Comment

by:suroma
ID: 31604255
That's spectacularly bad news!! Thanks for your help.
0
 
LVL 77

Expert Comment

by:Rob Williams
ID: 24872295
Thanks suroma.
It is a very common problem. Probably the most common problem on the VPN forums.
Cheers!
--Rob
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Cloud-based web filter/proxy - can it be done? What is the best software to use? 7 60
Clarification on Network "Usage" for ESXi host. 13 68
Dns issues 4 35
ASA Tunnel 18 30
In this article, I am going to show you how to simulate a multi-site Lab environment on a single Hyper-V host. I use this method successfully in my own lab to simulate three fully routed global AD Sites on a Windows 10 Hyper-V host.
I had an issue with InstallShield not being able to use Computer Browser service on Windows Server 2012. Here is the solution I found.
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question