RDP connection problems and mtu-test

[TPK]

Hello,

I am trying to diagnose a problem where the RDP sessions to my windows 7 workstation at work keeps disconnecting when I am trying to connect over the VPN..

I know its a VPN issue becuase when I connect directly to my workstation over the internet without the VPN (I set up a firewall rule to test this), I don't get the disconnection issues

Most of the posts I have read on the internet tell me its most likely a MTU issue, and some of the other posts on this forum say to use mtu-test and determine what the values for the "fragment" and "mssfix" options should be...

We have a corporate LAN, with an openVPN server running on a Windows Server 2003 virtual machine (perhaps the fact that it is running on a virtual machine may be a problem, but one thing at a time).. I am trying to connect from a laptop running Windows 7, via OpenVPN, and I am trying to the connect to my windows 7 workstation on the corporate LAN...

Anyhow, on the openVPN server, I try to put in the mtu-test option, and then I try to connect with my laptop openVPN client...

On the server, after a few minutes, I get this:

NOTE: failed to empirically measure MTU (requires OpenVPN 1.5 or higher at other end of connection).

This is confusing to me, because I know both sides are running a new release of OpenVPN, both sides are running 2.2.1 and in the log files of each I get this:

OpenVPN 2.2.1 Win32-MSVC++ [SSL] [LZO2] built on Jul 1 2011

... So how can I run the mtu-test?? Am I not doing it right??

I've attempted to fix the problem by setting the MTU on my TAP adapter to a value of 1000, but I still get disconnects on my RDP sessions after just a couple of minutes...

So I am not sure what to do... The RDP disconnects are really annoying, but one thing I found was that if I bring up a command prompt and permanently ping my corporate workstation I can solve the disconnect problem... Of course I would rather fix the issue without having to do that (and setting up command prompt windows to perma-ping all the workstations and servers I connect to is also rather tedious)....

Does anyone have any advice for me? Or somthing else I can try??

Yes, I have made sure that the power saving mode of the network adaptors on both sides are turned off, and yes I have made sure that the graphics drivers are updated...

[Mimiko]

Without specifying any mtu and mssfix I am not disconnected from RDP across OpenVPN tunnel. As you mentioned: if you set a ping, the RDP is not disconnected. So just add to your server's config "keepalive 20 120", for example.

[TPK]

Without specifying any mtu and mssfix I am not disconnected from RDP across OpenVPN tunnel. As you mentioned: if you set a ping, the RDP is not disconnected. So just add to your server's config "keepalive 20 120", for example.

Hello,

Yep, we have the keepalive in the config on the server, but it doesn't help... The disconnect is happening with the RDP session over the VPN, the VPN link itself remains stable and up, but its the RDP session from home PC to corporate workstation that gets disconnected...

Say if I have 2 RDP sessions up to 2 machines from home to the corporate LAN, I have to force a keepalive to BOTH machines from my home computer or whichever one(s) I am not pinging disconnect after a minute or so (so pinging one workstation, only keeps that particular workstation's RDP session alive)..

[Mimiko]

Try this http://answers.microsoft.com/en-us/wind ... be1e687eea