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gorlazFlag for Australia

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Can't connect to SBS server over Linksys VPN via TS

Hi all,

I've got a SBS2k3 server that I'm having issues connecting to.

I'm using a Linksys VPN client to get to the remote network which has a Satellite connection, and a dial up connection (due to firewall restrictions) on my end.

It seems to connect ok and I can ping the server which responds fine (pings anywhere from 1000ms to 3500ms!!). I have previously connected via this method with no issues.

After the VPN is established; I try to open an RDP session to the server address (10.0.0.1) and get the error after an incredibly long time;

Fatal Error (Error Code 5)
Session will be disconnected. Your computer may be low on memory. After closing try to reconnect.

My PC has plenty of memory available; so I'm wondering if its the remote SBS machine?

I want to connect to it for maintenance as well as enabling RWW so I don't have to go through this in the future.

Any ideas?
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Rob Williams
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>>"(pings anywhere from 1000ms to 3500ms"
VPN's typically require ping responses of 125ms or less for a stable connection. >50Ms is normal on a good connection. With slow response times there is a tendency to loose the connection as soon as you try to transport data back anforth. I assume you are doing this with the satellite connection. A copy of a post of mine from an earlier question:

Often times a VPN is not possible over a satellite connection for 2 reasons.
1) The basic design of satellite networks causes significant end to end propagation delays that results in ping replies which are often between 300 and 500ms which  drastically degrades performance (should be no more than 125ms)  
2) the satellite connection will often not support various encryption protocols such as PPTP and IPSec
A couple of articles explaining some of these difficulties:
http://compnetworking.about.com/od/vpn/f/vpnandsatellite.htm
http://www.agristar.com/satellite_vpn.shtml
http://forum.ecoustics.com/bbs/messages/34579/127542.html
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ASKER

Hi Rob,

Thanks for the info, I realise satellite is not an optimum solution, however it has worked previously in the past so the query was more if anyone else had had a similar issue and or the exact error message noted above. The pings now are exactly the same as they have been previously. Yes it is a sat connection.

It's as slow as heck and is like pulling teeth but it used to work and get the job done - whether something has changed I'm not sure which is the nature of the question.

Re the not being possible over sat;

1) Agreed, but it can and does work up to the noted latency's, you just need to be very patient, there have been no issues previously with RDP not working.
2) Agreed also, it depends on the satellite and the providers network infrastructure. Most of the time a public IP rather than the internal satellite one will allow VPN's as it is outside any restrcitions the ISP is using. The reason we received for needing it was that PPTP headers don't traverse sat connections well, they tend to get zapped.

ASKER CERTIFIED SOLUTION
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Rob Williams
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nitsud01

RobWill - Good info on VPN propagation times and such.... and.... I agree, this is a poor access method for what you are trying to do... I would try and find a new solution for connecting to your TS....

But, if that isn't an option.......

Your problem could be related to quite a few things...

First of all, what app is that error message being generated from? The windows RDP client (I've never seen it) or the Linksys VPN client?

Are any other users/clients who connect to your VPN/TS the same way as you do that have received similar errors recently? Are they working from the same physical location as the workstation in question? Are they using the same connection methods? Are they using the same client software? etc....?

Before you go any further, you need to isolate the problem to either the server, the client, or somewhere in between....

Try your same connection methods on a different client/workstation from the same physical location (if you have to, swap the computer for a different one with applicable apps installed).... Use same network connection if possible.... (Try to only change one variable at a time when troubleshooting)

Try connecting to the VPN and TS from a higher bandwidth connection.... Does the error appear?

Have any of the routers (that you have access to) in your network router been upgraded lately? Any other recent router configuration changes?

Mainly, if it worked before... Then it should work now.... Generally speaking, something must have changed somewhere causing this behavior.... :)

We just need to figure out what changed. Try and post as much info as you can stand :) It helps us help you.....

Cheers!

One thing that can cause these problems is your MTU setting.  While the default on most devices is 1500, PPTP doesn't like anything more than 1462.  The server may be set at 1400, but it'squite possible that your router is still at 1500.

See http://www.speedguide.net/faq_in_q.php?category=89&qid=162 and it's related links.

Jeff
TechSoEasy
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ASKER

Rob - perfect! For some reason - the first session wouldn't connect but the second did. Very strange, but I'll take a weird workaround anyday. I suspect its because of what Jeff posted but dont have access to check at the moment as they are off air.

nitsud01 - satellite is unfortunately a necessary evil - the remote location is very remote and can't get any other form of internet connection at all. Re your other questions; I'll answer to fill the blanks in for future users.

* Error occurs in what looks to the RDP client, VPN client has already connected fine by that stage.
* No other users connect the same way.
* Can't connect from another computer for security reasons; we limit what computers have external VPN access (it's something we try to stick to; there isn't anything to physically stop it however)
* Don't have access to a higher connection at the moment but could be tried later at another site.
* No routers been upgraded either firmware or hardware. No other router changes.
* Re worked before but not now - I know :) Hence my post to see if anyone else had come across the same issue.

Jeff: Thanks muchly - will check that at first opportunity.
Glad to hear it worked gorlaz.
Very odd indeed. Good to know, as frustrating as I am sure it is, that even with ping response times that slow you can still connect. I didn't think it was possible.
Thanks gorlaz,
--Rob
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ASKER

Lol - possible - yes; usable - sorta - you need a lot of time and patience :(
Thanks for the followup info, gorlaz!
>>"you need a lot of time and patience :("
Any connection is better than no connection  :-)